Earth working machine having a rotatable working apparatus axially positionally retainable with high tightening torque by means of a central bolt arrangement, and method for establishing and releasing such retention

ABSTRACT

An earth working machine encompasses a machine body having a machine frame and a drive configuration rotationally drivable relative to the machine frame around a drive axis (A). It further encompasses a working apparatus ( 32 ) for earth working to which the drive configuration is releasably connected in drive torque-transferring fashion for rotation together, the drive configuration projecting from an axial end axially into the working apparatus ( 32 ) and the working apparatus ( 32 ) being retained on the drive configuration, against axial displacement relative to the drive configuration, by an accessible central bolt arrangement having a bolt axis collinear with the drive axis (A). Provision is made according to the present invention that the earth working machine encompasses a bolting moment bracing arrangement ( 82 ) which is connected or connectable in bolting moment-transferring fashion to a bolt component, helically movable relative to the drive configuration, of the bolt arrangement, and which comprises a bracing region ( 82   e,    82   gf ) that is embodied for bolting moment-bracing abutment in a bracing bolting direction against a counterpart bracing region ( 84   b,    84   c ), the drive configuration being embodied to be driven to rotate, in a rotation direction codirectional with the bracing bolting direction, while the bracing region ( 82   e,    82   f ) is in abutment against the counterpart bracing region ( 84   b,    84   c ).

BACKGROUND OF THE INVENTION

The present invention relates to an earth working machine, such as aroad milling machine, a recycler, a stabilizer, or a surface miner andthe like. The earth working machine encompasses a machine body having amachine frame and a drive configuration rotationally drivable around adrive axis relative to the machine frame. The drive axis defines anaxial direction. The earth working machine further encompasses a workingapparatus for earth working to which the drive configuration isreleasably connected in drive torque-transferring fashion for rotationtogether. The working apparatus extends axially between a drive axialend and a retention axial end located oppositely from the drive axialend, and radially externally surrounds the drive configuration of theearth working machine. The working apparatus is retained on the driveconfiguration, against axial displacement relative to the driveconfiguration, by way of a central bolt arrangement that is accessiblein the region of its retention axial end and has a bolt axis collinearwith the drive axis.

An earth working machine of this kind, in the form of an earth millingmachine, is known from DE 10 2012 008 252 A1. This document discloses amilling drum constituting a working apparatus, which is retained in theregion of its retention axial end by way of a threaded rod screwed atthe end into the drive configuration, and a retaining nut in boltingengagement therewith. The milling drum of the known earth millingmachine is pushed axially with the retaining nut against a tooth set ina region located closer to the drive axial end of the milling drum. Adrive torque is transferrable by the tooth set from the driveconfiguration to the milling drum.

The axial positional retention of the milling drum relative to the driveconfiguration as known from DE 10 2012 008 252 A1 is disadvantageous interms of its retaining effect. Because of the use of a threaded rodscrewed at the end into the drive configuration and a retaining nut inbolting engagement with the threaded rod, upon release of axialpositional retention is not possible to predict the point at which thebolt arrangement begins to loosen upon exertion of a loosening torque(release moment). On the one hand, the threaded rod together with theretaining nut can be unscrewed from the drive configuration as a boltarrangement moving together; on the other hand, the retaining nut canmove relative to the threaded rod so that the threaded rod constitutes,with the drive configuration, an arrangement which is connected formovement together and relative to which the retaining nut is movable.

Lastly, as a function of differences in friction conditions, caused e.g.by dirt, upon exertion of a release moment, both the one and the othersituation can occur, so that in portions the threaded rod is unscrewedfrom the drive configuration, and in portions the retaining nut is movedrelative to the threaded rod. In either case, exertion of a looseningtorque does not result in an unequivocally predictable machine state.

The same can be true, mutatis mutandis, for a tightening torque(tightening moment) in a retaining direction, although the possibilitythat exists here, in contrast to loosening, is firstly to screw in thethreaded rod and only then bolt on the retaining nut.

In addition, because of the dimensions of the known retaining nut, thetorque that can be exerted on the bolt arrangement of the known millingdrum upon tightening and loosening using conventional tools, for examplea torque wrench, is limited. It is noteworthy here that earth-removingworking apparatuses in particular are exposed, while being operated asintended, to very large force inputs that an axial positional retentionsystem must withstand. Reliable establishment, and also reliablerelease, of axial positional retention for a working apparatus of anearth working machine is therefore the focus of the present Application.

The present invention therefore also relates to a method forestablishing or releasing axial positional retention of a workingapparatus of an earth working machine on a drive configuration of theearth working machine, in particular of the earth working machinerecited above. The drive configuration is rotatable around a drive axisrelative to a machine frame of the earth working machine. The workingapparatus radially externally surrounds the drive configuration, axialpositional retention being effected by a central bolt arrangement havinga bolt axis collinear with the drive axis.

Because of the potentially very large reaction forces that occurdepending on the kind of working, and that feed back into the workingapparatus in the context of earth working, axial positional retention ofthe working apparatus on the drive configuration with a tighteningtorque of more than 2500 Nm is desirable in order to furnish sufficientoperating reliability. Applying such a large retaining torque to thebolt arrangement of the earth milling machine known from DE 10 2012 008252 A1 is cumbersome, and requires tools that are usually available onlyin workshops but not at the utilization site of the machine.

SUMMARY OF THE INVENTION

The object of the present invention is therefore to describe a technicalteaching according to which the working apparatus is retainable in itsaxial position on the drive configuration by means of the central boltarrangement, in simple and reliable fashion, with a high tighteningtorque.

According to a first aspect of the present invention this object isachieved in that the method recited initially additionally encompassesthe following steps:

-   -   bracing a bolt component, boltable relative to the drive        configuration, of the bolt arrangement to prevent a rotational        movement of the bolt component in a bracing bolting direction;        and    -   driving the drive configuration to rotate in a rotation        direction codirectional with respect to the bracing bolting        direction.

In terms of apparatus the aforesaid object is achieved, in accordancewith a second aspect objectively correlated with the first, by an earthworking machine of the kind recited initially which is embodied toexecute the aforementioned method according to the present invention.

In terms of design, the embodiment of the earth working machine forexecuting the aforesaid method can be implemented by the fact that theearth working machine encompasses a bolting moment bracing arrangementwhich is connected or connectable in bolting moment-transferring fashionto a bolt component, helically movable relative to the driveconfiguration, of the bolt arrangement, and which comprises a bracingregion that is embodied for bolting moment-bracing abutment in a bracingbolting direction against a counterpart bracing region, the driveconfiguration being embodied to be driven to rotate, in a rotationdirection codirectional with the bracing bolting direction, while thebracing region is in abutment against the counterpart bracing region.

The basic idea of the present invention is to use the driveconfiguration to apply to the central bolt arrangement a sufficientlyhigh tightening torque upon establishment of axial positional retentionand/or a sufficiently high loosening torque upon release of axialpositional retention. The source of torque for a tightening and/orloosening torque acting on the bolt arrangement is therefore not, aspreviously in the sector of earth working machines, a torque wrench oran impact driver in the form of a mechanized torque wrench that engagesdirectly onto the bolt arrangement, but instead is the driveconfiguration, or a source of drive force connected intorque-transferring fashion to the drive configuration.

The bolt configuration can therefore be sufficiently dimensioned that itcan be used as the only axial positional retention system of the workingapparatus. Bolting moments of 2500 Nm and more can therefore beintroduced into the bolt configuration. Tools introducing a high torque,which are laborious and complex to operate, are not required accordingto the present invention, since the drive configuration and its sourceof drive force are used to apply the bolting moment onto the boltconfiguration.

With the working apparatus in the operational state the driveconfiguration preferably does not project axially beyond its retentionaxial end, so that the working apparatus can be brought at its retentionaxial end as close as possible to the edge of the remainder of themachine body. The working apparatus preferably projects axially beyondthe drive configuration on at least one side, for example with itsretention axial end. Particularly preferably, the working apparatusprojects axially beyond the drive configuration on both sides.

Unless otherwise stated in individual cases, the present Applicationdescribes the earth working machine in a state ready for earth workingas intended.

Although it is preferred in the context of the present Application thatthe central bolt arrangement exclusively effect axial positionalretention, “effecting” of axial positional retention by the central boltarrangement is intended already to be implemented if the central boltarrangement contributes to axial positional retention. The additionalimplementation of one or several further retaining measures in additionto the central bolt arrangement is therefore not to be excluded.

Furthermore, be it noted directly at this juncture that unless otherwiseindicated, the drive axis of the drive configuration is the referencemagnitude for the “axial” and “radial” indications utilized in thepresent Application. A direction parallel to the drive axis is thereforean axial direction, and a direction proceeding orthogonally thereto is aradial direction.

The present Application discusses “drive torque” and “bolting moment.”This terminology is used merely for better differentiation of torques interms of their respectively considered location of action. The differentterms are used in particular when drive torques introduced on the driveside into the drive configuration, and bolting moments occurring at thebolt configuration, are recited in close proximity to one another in thetext. They are always torques. No essential difference exists betweenthe torques that are thus differently characterized. A braced boltingmoment thus can, and does, occur according to the present invention as areaction to a drive torque introduced on the drive side.

The machine frame, constituting the basic structural unit of the earthworking machine, forms a kind of basic reference system of the machine.The machine body encompasses the machine frame and further machine partsconnected, including movably connected, thereto.

The drive configuration is usually coupled to a drive motor of the earthworking machine, although the drive motor as a rule has a higherrotation speed than the rotation speed required at the driveconfiguration in the context of earth working as intended. Atransmission that steps a rotation speed down, and thus steps torque up,is therefore usually operatively connected to the drive configuration.The drive configuration preferably encompasses part of the transmissionhousing of the transmission, and particularly preferably, when thetransmission is embodied in space-saving fashion as a planetary gearset,is coupled to a ring gear of the transmission for rotation together.This transmission can advantageously be utilized in order to amplify adrive torque transferred on the drive side to the drive configuration,and thus, as a result of the torque step-up that is accomplished, toeffect at the location of the bolt arrangement, with a comparatively lowdrive torque outputted by the drive motor or by a rotational drive,including a manual rotational drive, embodied separately therefrom, atightening and/or loosening moment, constituting a bolting moment, whichis multiplied by an amount equal to the conversion ratio. All that isnecessary for this purpose is to brace the bolt component, helicallymovable relative to the drive configuration, of the bolt arrangement soas to prevent it from co-rotating with the driven drive configuration.

It is usually substantially simpler in terms of apparatus simply tobrace a predefined large bolting moment at a bolt arrangement than toactively introduce a bolting moment of the same magnitude into the boltarrangement by way of an operator.

Be it noted at this juncture that refinements of the earth workingmachine explained in the present Application are also to be understoodas refinements of the method according to the present invention, andvice versa.

The counterpart bracing region against which the bolting moment bracingarrangement braces during exertion of a tightening or loosening momentcan be any region that is at rest relative to the machine body. Becausethe earth working machine, which advantageously is self-propelled in amanner known per se, is stationary during establishment or release ofaxial positional retention of the working apparatus, relative to thecontact substrate on which the earth working machine is currentlystanding, the counterpart bracing region can also be constituted by aregion of the substrate.

But because the nature of the substrate carrying the earth workingmachine can be very different depending on where the earth workingmachine is being utilized, and can therefore also be unsuitable forbolting moment-bracing abutment of the bracing region of the boltingmoment bracing arrangement, for example because it is too soft, thecounterpart bracing region is preferably provided on the machine body.

The bolting moment bracing arrangement can be connected, for examplenonreleasably, to the bolt component. It can be embodied, for example,in one piece with the bolt component. In that case it is necessary toprovide the counterpart bracing region releasably on the machine body sothat it is arranged on the machine body only when it is actually neededin order to brace a tightening moment or loosening moment exerted by thedrive configuration. Because the working apparatus must be capable,during earth-working operation thereof as intended, of rotating relativeto the machine frame without influencing positional retention of theworking apparatus by the bolt arrangement, provision of the counterpartbracing region on the machine body at times other than establishment orrelease of axial positional retention could be detrimental to operation.

A connection is “releasable” for purposes of this Application when it isreleasable without destroying components involved in the connection. Athreaded connection or bolted connection or clamp or a positive bayonetconnection are examples of releasable connections.

According to a preferred refinement of the present invention, the earthworking machine can comprise one or several sensors that query theposition of the bolting moment bracing arrangement and/or of thecounterpart bracing region in a stowed position on the machine and/orthe position of the bolting moment bracing arrangement and/or of thecounterpart bracing region in a bracing-capable position, and the like.A machine controller of the earth working machine is preferablyconnected to the at least one sensor and is configured so as to permitearth-working operation of the machine as intended only when thedetection signal or signals transferred from the at least one sensorindicate that a collision between the bolting moment bracing arrangementand the counterpart bracing region is precluded.

Conversely, if the at least one sensor signal indicates a collisionrisk, the maximum power outputtable by the drive motor can be limited toa value reduced with respect to the rated output during earth-workingoperation, or the drive motor can be shut off and the introduction oftorque into the drive apparatus can be limited to a rotational drive,including a mechanical rotational drive, embodied separately from thedrive motor.

The counterpart bracing region is preferably implemented on acounterpart bracing component. Even if the bolting moment bracingarrangement is not connected permanently to the bolt component butinstead is connectable to it as necessary, a counterpart bracingcomponent of this kind can be releasably connected to the machine frame,or to the remainder of the machine body, for repair, maintenance, andreplacement purposes. As a result of the releasable connectability ofthe bolting moment bracing arrangement to the bolt component, however,in order to decrease installation complexity the counterpart bracingcomponent can also be provided on the machine body, and/or connected toit, during operating phases of the earth working machine as intended.

In many cases an encasing component is arranged on the earth workingmachine for industrial safety reasons, at a distance oppositely from theretention axial end in a direction away from the drive axial end, sothat the working apparatus is not accessible in an axial directionduring phases of earth-working operation as intended. Because the boltarrangement is preferably located closer to the retention axial end thanto the drive axial end of the working apparatus, the counterpart bracingregion can easily and advantageously be provided on an encasingcomponent of this kind, e.g. in the form of the counterpart bracingcomponent, for example (in order to furnish sufficient strength) as asheet steel component that is connected to the encasing component. Thecounterpart bracing component can preferably comprise a passthroughopening through which at least the bolt component of the boltarrangement is accessible.

In the preferred case of a milling drum or milling rotor constitutingthe working apparatus, the latter is usually located, in a manner knownper se, in a milling drum housing that shields the working apparatus notonly at the ends but also in and oppositely to the longitudinal machinedirection of the earth working machine. The known encasing component canbe part of such a milling drum housing. It can be movable relative tothe machine frame and to the remainder of the machine body, for exampleconnected removably or pivotably movably to the machine frame, so as toenable rapid and simple changing of the working apparatus after releaseof the bolt arrangement. As a rule, the working apparatus and themachine body are moved away from or toward one another axially in orderto change the working apparatus.

According to an advantageous refinement of the present invention, theencasing component is connected pivotably movably to the machine frame,a non-locating bearing that mounts the working apparatus for rotationaround the drive axis being connected to the encasing component formovement together. It is thus possible, with the pivoting movement ofthe encasing component from a closed position in which the encasingcomponent shields the working apparatus and/or the drive configurationfrom external access, into an access position in which the workingapparatus and/or the drive configuration are axially accessible, for thenon-locating bearing to be pulled off a corresponding bearingconfiguration of the working apparatus or of the drive configuration.

The non-locating bearing is referred to as a “non-locating” bearingbecause it mounts a bearing configuration of the working apparatus or ofthe drive configuration rotatably around the drive rotation axis butdisplaceably along the drive rotation axis. A change caused, for examplethermally, in the length of the bearing components (non-locating bearingand bearing configuration) involved in the non-locating bearing point,and/or of the components that are mounted, is thus possible withoutresulting in excessively large mechanical stresses in the componentsinvolved. With the earth working machine in the operational state, thenon-locating bearing as a rule is located axially closer to theretention axial end of the working apparatus than to its drive axialend. A locating bearing that is provided, with the exception of alocating bearing component rotatable around the drive axis, on themachine frame immovably relative to the machine frame and is providedfor rotational mounting of the working apparatus and, as a rule, alsothe drive configuration around the drive axis, is usually located closerto the drive axial end than to the retention axial end.

It is known from DE 40 37 448 A1 to move the non-locating bearing,together with a planar encasing component that is part of a milling drumhousing, translationally along the drive axis away from or toward theworking apparatus in the form of a milling drum. It is necessary forthat purpose, however, to remove the encasing component completely fromthe machine frame, which entails a considerable installation outlay.

Provision is made more advantageously, in accordance with a refinementof the present invention, to provide the encasing component pivotablymovably on the machine frame. The non-locating bearing connected to theencasing component for pivoting movement together can thus, by apivoting movement of the encasing component, be pulled off the bearingconfiguration of the working apparatus or the drive configuration and/orslid onto the bearing configuration, depending on the pivotingdirection. This is because the encasing component articulated pivotablyon the machine frame can remain connected in lossproof fashion to themachine frame and can thereby, with repeatable accuracy, guide apulling-off movement of the non-locating bearing from the bearingconfiguration characterized above, or a sliding-on movement onto such abearing configuration.

Regardless of the above-described advantageous refinement of the presentinvention, the pivoting movement of the non-locating bearing of theworking apparatus together with the encasing component providedpivotably movably on the machine frame imparts particular value to anearth working machine because of the resulting considerably simplifiedcapability for installing and removing the working apparatus onto andfrom the machine body. The present Application therefore also relates toan earth working machine, for example a road milling machine, arecycler, a stabilizer, or a surface miner and the like, encompassing amachine body having a machine frame and a drive configurationrotationally drivable around a drive axis, defining an axial direction,relative to the machine frame, the earth working machine encompassing aworking apparatus for earth working to which the drive configuration isreleasably connected in drive torque-transferring fashion for rotationtogether, the working apparatus extending axially between a drive axialend and a retention axial end located oppositely from the drive axialend and radially externally surrounding the drive configuration of theearth working machine, an encasing component that is connected pivotablymovably to the machine frame and carries a non-locating bearing, whichmounts the working apparatus for rotation around the drive axis and isconnected to the encasing component for pivoting movement together,being arranged oppositely from the retention axial end, at a distancefrom the retention axial end in a direction away from the drive axialend, with the earth working machine in the operational state.

The non-locating bearing can mount the working apparatus directly, orindirectly via the drive configuration, for rotation around the driveaxis.

According to a preferred refinement in order to achieve the advantagesrecited above, the working apparatus of this earth working machine canbe retained on the drive configuration, against axial displacementrelative to the drive configuration, by way of a central boltarrangement, accessible in the region of its retention axial end, havinga bolt axis collinear with the drive axis.

The advantageous refinements described below relate to all the earthworking machines described in the present Application.

The non-locating bearing preferably comprises a recess into which abearing stem, constituting the bearing configuration of the driveconfiguration or of the working apparatus, projects with the earthworking machine in the operational state. The bearing stem is preferablyprovided in a region located closer to the retention axial end of theworking apparatus than to the drive axial end, and extends in an axialdirection away from the drive axial end. The bearing stem preferablyprotrudes axially out of a protrusion structure carrying it. When thebearing stem is connected to the working apparatus to rotate together,the protrusion structure can be, for example, a flange configuration byway of which a component comprising the bearing stem is connected,preferably releasably connected, to the working apparatus.Alternatively, when the bearing stem is connected to move together withthe drive configuration, the protrusion structure can be an end plate ofthe drive configuration from which the bearing stem passes centeringly,along the drive axis, through a connecting flange of the workingapparatus.

Because the non-locating bearing on the one hand mounts the bearing stemaxially displaceably for rotation around the drive axis, but on theother hand is intended to be slid onto the bearing stem or pulled off itby way of a pivoting movement that deviates from the drive rotation axisbecause it follows a curved trajectory, the design-related relativemovability of the bearing stem and non-locating bearing, and the actualrelative movement of the bearing stem and non-locating bearing whilebeing slid on and pulled off, do not match. The result, in the contextof sliding the non-locating bearing onto, and pulling it off, thebearing, is a risk of an undesired collision between the bearing stemand the non-locating bearing.

In order to achieve a collision-free, or at least low-collision,pivoting movement of the non-locating bearing together with the encasingcomponent, the bearing stem is preferably embodied to taper axially in adirection away from the drive axial end. Additionally or alternatively,the recess of the non-locating bearing is embodied to widen axially in adirection toward the working apparatus.

For maximally stable mounting of the bearing stem on the non-locatingbearing, the bearing stem comprises preferably at least two,particularly preferably exactly two, cylindrical bearing surfaces at anaxial distance from one another, which are surrounded with zeroclearance by hollow-cylindrical counterpart bearing surfaces of thenon-locating bearing when the earth working machine is in theoperational state. In order to simplify sliding or pivoting of thenon-locating bearing onto the bearing stem by way of a pivoting movementof the non-locating bearing, the cylindrical bearing surface locatedaxially farther from the protrusion structure preferably has a smallerdiameter than the cylindrical bearing surface located axially closer tothe protrusion structure. What has been stated with regard to thecylindrical bearing surfaces is correspondingly true, mutatis mutandis,for the hollow-cylindrical counterpart bearing surfaces of thenon-locating bearing which surround and are in contact with thecylindrical bearing surfaces of the bearing stem with the earth workingmachine in the operational state.

A particularly advantageous embodiment of the bearing stem which enablesa pull-off and slide-on movement, accompanying the pivoting movementtogether of the non-locating bearing and encasing component, of thenon-locating bearing respectively from and onto the bearing stem inparticularly low-collision fashion will be explained below withreference to notional cones that envelopingly surround portions of thebearing stem. According to a preferred embodiment, the axially taperingconformation of the bearing stem is such that the opening angle of twonotional enveloping cones that respectively abut tangentially againsttwo osculating circles, located at an axial distance from one another,on the surface of the bearing stem and surround an axial portion of thebearing stem located between the osculating circles, is smaller forcones of osculating circle pairs located closer to the protrusionstructure. The osculating circles abut respectively against the radialouter surface of the bearing stem.

In design terms, as a concrete example of an advantageous refinement ofthe present invention, the bearing stem can comprise a smaller-diameterfirst cylindrical bearing surface farther from the protrusion structureand a larger-diameter second cylindrical bearing surface closer to theprotrusion structure.

Assume a first notional enveloping cone whose first osculating circle,located farther from the protrusion structure, is placed at the freeaxial longitudinal end located remotely from the protrusion structure,and whose second osculating circle, located closer to the protrusionstructure, is located axially between the first osculating circle andthe axial longitudinal end, located closer to the free bearing stemlongitudinal end, of the first cylindrical bearing surface. The latterlongitudinal end is explicitly part of the axial region delimiting it,and can therefore be a site of the second osculating circle.

Assume further a second notional enveloping cone whose first osculatingcircle, located farther from the protrusion structure, is placed at theaxial longitudinal end, located closer to the free bearing stemlongitudinal end, of the first cylindrical bearing surface. At thischaracteristic first osculating circle, constituting the beginning ofthe second notional cone, the second notional cone can abut tangentiallyagainst the outer surface of the bearing stem but does not need to doso. The second osculating circle of the second notional cone is locatedaxially between its first osculating circle and the axial longitudinalend located closer to the free bearing stem longitudinal end, includingthat longitudinal end, of the second cylindrical bearing surface. Withthe exception of the first osculating circle of the second notionalcone, the two notional cones abut tangentially against all theosculating circles at the outer surface of the bearing stem.

Under the conditions recited above, the bearing stem is embodied forlow-collision sliding-on and pulling-off movement of the non-locatingbearing if the first notional cone has a larger opening angle than thesecond notional cone.

The following exceptions are to be noted: If the free longitudinal endof the bearing stem has a bevel, the bevel edge located axially closerto the protrusion structure is to be employed as the first osculatingcircle of the first notional cone. If the bevel edge located axiallycloser to the protrusion structure is itself the axial longitudinal end,located closer to the free bearing stem longitudinal end, of the firstcylindrical bearing surface, the cone of the bevel then constitutes thefirst notional cone. The bevel angle is then its opening angle.

The opening angle of the first notional cone is preferably equal to atleast 1.5 times the opening angle of the second notional cone,particularly preferably at least 2.5 times. Also preferably, the openingangle of the second notional cone is equal to 5° to 15°, particularlypreferably 8° to 13°.

A comparatively larger opening angle of the first notional cone allowsthe free bearing stem longitudinal end to be captured even if thelocation of the longitudinal axis of the bearing stem, with thenon-locating bearing pulled off, differs greatly from the ideal locationof the drive axis because of the dead weight of the working apparatusand/or of the drive configuration.

The smaller opening angle of the second notional cone compared with theopening angle of the first notional cone makes it possible, aftercapture of the free bearing stem longitudinal end, to slide thenon-locating bearing onto the bearing stem in the course of the pivotingmovement of the non-locating bearing relative to the bearing stem.

In principle, the drive axis can be oriented arbitrarily on the machinebody; preferably it is oriented parallel to the contact substrate sothat a homogeneous working engagement of the working apparatus with theground can be brought about over the axial extent of the workingapparatus. The drive axis is preferably oriented in a transverse machinedirection of the working machine, so that the working apparatus can beadvanced relative to the ground orthogonally to the drive axis by atravel drive of the earth working machine.

Bolting moment bracing that is both simple and effective can be achievedby way of a positive engagement between the bracing region andcounterpart bracing region. A frictional engagement is theoreticallyalso conceivable, but positively engaging bracing is preferred becauseof the aforementioned large tightening and loosening moments. Provisioncan be made concretely, for this purpose, that one region from among thebracing region and counterpart bracing region comprises at least oneprojection, and that the respective other region from among the bracingregion and counterpart bracing region comprises at least one recess intowhich the projection projects.

Because the counterpart bracing region advantageously can be arranged,because of the available installation space, in such a way that itradially externally surrounds the bolt component or, when there is anaxial offset therefrom, is provided at least radially outside the radialextent, if applicable considered to be axially prolonged, of the boltcomponent, preferably the projection is embodied on the bracing regionand the recess on the counterpart bracing region. Because permanentarrangement of both the bracing region and the counterpart bracingregion on the earth working machine as a rule is disadvantageous interms of operation of the earth working machine for the reasons recitedabove, one of the two regions is, as already set forth in conjunctionwith the counterpart bracing region, removable from the earth workingmachine after establishment or release of axial positional retention. Inorder to facilitate the placement and/or removal of the bracing regionand counterpart bracing region relative to one another on the earthworking machine, preferably the recess is embodied to be larger than theprojection, so that an exact relative rotational position of the driveconfiguration relative to the machine frame is unimportant in terms ofthe arrangement of one or both regions on the earth working machine.Preferably the recess is a radial recess, with reference to the extendedimaginary drive axis, which extends around the drive axis in acircumferential direction over a larger angular region than theprojection interacting with it.

The bolt component can be a nut or a bolt. The bolting moment bracingarrangement can then, as already indicated above, be embodied in onepiece with the bolt component, for example if at least one projectionprojects radially and/or axially from the bolt component, e.g. from thenut or from the bolt head, as is known, for example, from wing nuts andthumbscrews. That projection is then conveyable into abutting engagementwith a contour delimiting the recess of the counterpart bracing region.

The installation and deinstallation of the counterpart bracing regionwhich are then necessary can, however, entail an undesired installationcomplexity. It is therefore preferred that the bolting moment bracingarrangement be embodied as a tool arrangement, separate from the machinebody and from the bolt arrangement, having an engagement region that isembodied for releasable torque-transferring engagement with acounterpart engagement region of the bolt component.

The aforementioned method can correspondingly be refined in that thebracing step encompasses the following sub-steps:

-   -   connecting an engagement region of a bolting moment bracing        arrangement, embodied separately from the machine body, to a        counterpart engagement region of the bolt component for torque        transfer between the bolting moment bracing arrangement and the        bolt component; and    -   arranging a bracing region of the bolting moment bracing        arrangement for bolting moment-bracing abutment against a        counterpart bracing region, preferably against a counterpart        bracing region on the machine body.

Although the counterpart engagement region of the bolt component canhave any conformation, it is advantageous to use as a counterpartengagement region a tool engagement configuration usually present in anycase on bolt components, for example a polyhedral configuration, such ase.g. a known hex head or hex socket configuration, and the like. Theadvantage of the separate embodiment of the bolting moment bracingarrangement is that it can be embodied in that case with a comparativelysmall physical volume, and can be carried along in stowed fashion on theearth working machine when not in use. For example, the bolting momentbracing arrangement can be slid with its engagement region axially ontoat least a portion of the bolt component and pulled off it again, forexample in the manner of a fitover tool as known from socket wrenches.The engagement region is therefore preferably embodied as a fitoverengagement region on the bolting moment bracing arrangement, whichregion, particularly preferably when engagement is established,continuously surrounds the counterpart engagement region in acircumferential direction around the drive axis.

In accordance with an advantageous refinement of the invention provisioncan then be made that, when viewing the bolting moment bracingarrangement with engagement established between the engagement regionand counterpart engagement region, the at least one projection projectsradially from an engagement portion, comprising the engagement region,of the bolting moment bracing arrangement.

A test apparatus, which is embodied to check the magnitude of a torqueacting between the bracing region and the engagement region, can beprovided in the torque transfer path between the bracing region and theengagement region in order to monitor the bolting moment exerted on thebolt arrangement. It is sufficient in this context if the test apparatusis embodied to check that a predetermined or predeterminable ratedbolting moment, or a predetermined or predeterminable rated bracingmoment, has been reached. The test apparatus can therefore be atorque-transferring connection, acting in load-dependent fashion,between the bracing region and the engagement region, i.e. for examplebetween the at least one projection and the engagement portion. The testapparatus can thus be a coupling that acts in load-dependent fashion,for example a slip coupling, which transfers a torque up to thepredetermined or predeterminable limit value and, upon exertion of atorque higher than the limit torque, severs the torque-transferringconnection between the bracing region and the engagement region, forexample by slipping.

Additionally or alternatively, the test apparatus can be embodied tooutput a signal, preferably a “click” already known from torquewrenches, when the predetermined or predeterminable limit bolting momentor limit bracing moment is reached. When the limit moment of the testapparatus corresponds to the desired rated bolting moment or correlatesin a desired manner with it, the bolt arrangement can then beeffectively and reliably tightened on the bolting moment bracingarrangement, with simple means, with a desired rated tightening moment.Loosening, conversely, as a rule does not require any detection of abolting moment, since all that is important then is to release axialpositional retention regardless of the magnitude of the bolting momentrequired for that purpose.

In order to brace the aforementioned large tightening or looseningmoment, it can be advantageous to provide more than one projection onthe bolting moment bracing arrangement so that at least two projectionscan project from the engagement portion. To allow the projections to bebrought into stable positive abutting engagement with a correspondingabutment contour of the counterpart bracing region, it is advantageouson the other hand not to make the recess in the counterpart bracingregion too large, and thereby not to excessively weaken the counterpartbracing region and the component embodied in it. The at least twoprojections are therefore preferably located diametrically opposite oneanother with respect to the drive axis when engagement is establishedbetween the engagement region and counterpart engagement region. For thereasons recited, particularly preferably exactly two projections areprovided on the bolting moment bracing arrangement. These shouldpreferably project at least radially in order to be able to constitute aload arm sufficient for bracing large bolting moments. If necessary,however, they can additionally also project axially, for example in adirection away from the drive axial end when engagement is established.

For introduction of a drive torque into the drive configuration,provision can be made that the drive configuration is connected to adrive torque-transferring arrangement. The drive torque-transferringarrangement is provided for transferring drive torque to the driveconfiguration. The drive torque-transferring arrangement is coupled forthat purpose to a drive motor of the earth working machine and/orcomprises a coupling configuration for temporary coupling to therotational drive, already mentioned above, embodied separately from thedrive motor of the earth working machine.

In principle, the drive motor of the earth working machine, which motoris present in any case and drives the working apparatus to operate asintended, can be used as a source of drive force for exerting thetightening or loosening moment. This is possible in particular when, asis possible e.g. with smaller earth working machines, a drive motorwhose output can be regulated within wide limits is present, for examplean electric motor or a hydraulic motor.

Regardless of the conformation of the drive motor of the earth workingmachine, however, it is always possible to use a rotational drive,including a manual one, which is embodied separately from the drivemotor and can be temporarily coupled to the aforesaid couplingconfiguration for transfer of a torque. The coupling configuration canbe implemented on a component that can be part of the drivetorque-transferring arrangement between the drive motor and the driveconfiguration, or can be part of a further drive torque-transferringarrangement that serves only to transfer drive torque from the separaterotational drive.

In addition or alternatively to the above-described bracingarrangement-side test apparatus, a drive-side test apparatus can beprovided on the drive side of the drive configuration in order toascertain a bolting moment, in particular a tightening moment, that isactually being exerted. A mechanical drive-side test apparatuscorresponding to the above-described bracing arrangement-side testapparatus, including in terms of the physical principles of actionutilized, can be arranged or at least arrangeable in the drivetorque-transferring arrangement. The description above of the bracingarrangement-side test apparatus correspondingly applies in that regardto the mechanical drive-side test apparatus. A mechanical drive-sidetest apparatus permanently arranged in the drive torque-transferringarrangement between the drive motor and drive configuration canpreferably be switched on and off for undisrupted earth working, forexample by raising the limit moment value of the test apparatus abovethe drive torque values that are transferred in the drivetorque-transferring arrangement in the context of earth working asintended.

Additionally or alternatively, a drive-side test apparatus can detect atleast one variable characterizing energy delivery to the drive motor or,in particular, to the separate rotational drive, during drive torqueintroduction into the drive configuration with the bolt arrangementbraced, and infer therefrom the drive torque introduced during energydelivery. In the context of utilization of a hydraulic rotational drive,this is expressly intended to include detection at least of the pressureof the hydraulic fluid delivered to the rotational drive during drivetorque introduction. The drive-side test apparatus can therefore beprovided in a hydraulic line of the earth working machine which isembodied as a supply line for connection of a hydraulic rotationaldrive. Based on the known torque transfer relationships between the testapparatus detection site and the bolt arrangement site, it is againpossible to infer the bolting moment, in particular the tighteningmoment, from the drive torque.

The drive-side test apparatus can be connected to a machine controllerof the earth working machine which, for example on the basis ofcharacteristics diagrams and/or value tables stored in a memoryapparatus, ascertains from a detected value of the test apparatus thebolting moment associated therewith, and outputs it to the vehicledriver via an acoustic and/or optical signal. The machine controller canalso indicate, on the basis of the detected value of the test apparatus,that a rated bolting moment has been reached.

In a manner known per se, the machine controller of the earth workingmachine can utilize electronic circuits and can comprise microprocessorsand/or a stored-program control system as well as a data memory coupledthereto in data-transferring fashion.

The drive torque-transferring arrangement is preferably connected, forthe transfer of torque, to that longitudinal end of the driveconfiguration which is located closer to the drive axial end of theoperational working apparatus than to the retention axial end. Thismakes possible advantageous bracing of the bolting moment on one side ofthe earth working machine, and introduction of a drive torque on theother side, located oppositely with respect to the drive axis, of theearth working machine.

For the reasons recited above, the aforementioned transmission thatreduces drive rotation speed and increases drive torque is preferablylocated in the torque transfer path between the coupling configurationand the drive configuration.

In order to provide good dimensional stability simultaneously withminimum weight, the drive configuration is preferably at least inportions a hollow body, in particular a body embodied in tubular fashionat least over an axial portion. It can taper toward its longitudinal endthat is located closest to the retention axial end when the earthworking machine is in the operational state. In the region of thatlongitudinal end, preferably at the longitudinal end itself, the driveconfiguration can comprise a drive torque-transferring couplingarrangement for drive torque-transferring coupling to a counterpartcoupling arrangement of the working apparatus. In order to transfer themaximum possible drive torques, the coupling arrangement is preferablyconveyable into, and releasable from, positive engagement with thecounterpart coupling arrangement.

Not infrequently in the context of earth working machines, the aforesaidtransmission increases a drive torque inputted into it on the input sideby a factor of 10 or more on the output side. The separate rotationaldrive, which is preferably an electrical or pneumatic drive, cantherefore also be a manually operated torque wrench, since with theinterposed torque-step-up transmission it is easily possible to achieve,with input torques of 250 Nm or more, 2500 Nm or more at the engagementpoint between the drive configuration and bolt arrangement.

With respect to the statements made above regarding the apparatus, apreferred refinement of the method recited above correspondinglyprovides that it encompasses, before the drive configuration is driven,releasable coupling of the drive configuration to a rotational driveembodied separately from the drive motor of the earth working machine.

In order not only to achieve axial positional retention of the workingapparatus relative to the drive configuration using the driveconfiguration and the bolt arrangement, but also to be able to ensuretherewith that a central apparatus axis of the working apparatus iscollinear, within the context of the requisite accuracy, with the driveaxis of the drive configuration in the completely installed state,provision is preferably further made that the drive configurationcomprises, at its longitudinal end closer to the retention axial end, acentering configuration that is embodied for positive centeringengagement with a counterpart centering configuration connected rigidlyto the working apparatus. As a rule, the centering configuration is notthe only centering system for the working apparatus with respect to thedrive configuration. A second centering system is usually provided at anaxial distance from the centering configuration.

Although in principle any type of centering configuration can be used, acentering stem of the drive configuration, projecting axially from thedrive configuration in a direction away from the drive axial end, ispreferred, since with this centering stem a threaded bore of sufficientaxial length for bolting engagement with the bolt arrangement can befurnished.

Embodiments of the earth working machine according to the presentinvention can be embodied in such a way that the centering stem is, orcomprises, the aforementioned bearing stem interacting with thenon-locating bearing for rotational mounting of the working apparatus.

The counterpart centering configuration connected rigidly to the workingapparatus is, accordingly, preferably a centering recess into which thecentering stem projects, optionally in pass-through fashion, with theworking apparatus in the completely installed state, and whichpreferably contacts the centering stem circumferentially. The centeringstem preferably tapers toward its protruding longitudinal end; alsopreferably, the centering recess tapers in the same direction, so thatwhen the centering recess is slid axially onto the centering stem,self-centering of the counterpart centering configuration on thecentering stem results from the axial relative movement.

According to a particularly preferred embodiment of the presentinvention, the centering stem tapers in stepped form toward itsprotruding longitudinal end, and comprises a smaller-diameterpre-centering stem portion located axially farther from the driveconfiguration, as well as a larger-diameter main centering stem portionlocated axially closer to the drive configuration. The pre-centeringstem portion can serve to “load” the centering stem into the centeringrecess, and can thus serve for pre-centering alignment of the workingapparatus on the drive configuration in the context of installationthereof, for example so as to arrange the working apparatus in apreparation position explained in more detail below, and then to allowit to be displaced, based on the pre-alignment already accomplished,axially from the preparation position into the operational operatingposition under facilitated conditions.

The possible radial deviation of the rotation axis of the workingapparatus from the drive rotation axis thus decreases as the workingapparatus axially approaches its operating position. This centering ofthe working apparatus with respect to the drive rotation axis is broughtabout by the physical engagement of the centering stem, embodied asdescribed above, into the centering recess, and by the axial approach ofthe working apparatus toward its operating position. The displacementforce needed in order to bring the working apparatus closer to itsoperating position on the one hand depends on the radial distance to becovered between the rotation axis of the working apparatus and the driverotation axis, and on the other hand depends on the physicalconformation of the surfaces that interact with one another (outersurface of the centering stem and inner surface of the centeringrecess).

In the operating position, the working apparatus is centered relative tothe drive configuration, preferably exclusively, by the main centeringstem portion, which is centeringly surrounded by a main centering recessportion of the centering recess. With the working apparatus in theoperating position. the pre-centering stem portion is likewisesurrounded by a pre-centering recess portion of the centering recess.For easier placement of the centering stem in the centering recess, alarger radial clearance is present between the pre-centering stemportion and the pre-centering recess portion than between the maincentering stem portion and the main centering recess portion. Thisincludes a radially zero-clearance abutment of the main centering stemportion and main centering recess portion.

For easier displacement of the working apparatus into its operatingposition, according to a preferred refinement of the present inventionthe centering recess can be embodied with an opening angle thatdecreases along its taper. The opening angle can decrease in steps.

A preferred embodiment of the centering recess will again be describedon the basis of cones that abut in contacting, but not penetrating,fashion respectively at two contact circles located with an axialspacing from one another. Axially outside its contact circles, a conecan penetrate through the inner surface of the centering recess. Todifferentiate these cones from the notional cones used above to describea preferred external conformation of the bearing stem, the cones used todescribe the internal conformation of the centering recess will bereferred to as “virtual” cones.

Assume a first virtual cone that abuts against the edges, locatedaxially closest to the drive axial end, respectively of the maincentering recess portion and of the pre-centering recess portion.

Assume further a second virtual cone that abuts on the one hand againstthat edge of the pre-centering recess portion which is located axiallyclosest to the drive axial end, and on the other hand against an edge,located closest to the drive axial end, of a radial shoulder of thecentering recess axially following the pre-centering recess portion in acentering stem penetration direction, or of a recess of which thecentering recess is a part.

The working apparatus can be brought axially closer to the operatingposition, accompanied by introduction of the centering stem into thecentering recess, with particularly low displacement forces when thefirst virtual cone has a larger opening angle than the second virtualcone.

The opening angle of the first virtual cone is preferably between 20°and 40°, particularly preferably between 25° and 35°. Also preferably,the opening angle of the first virtual cone is between 3 and 6 times,particularly preferably 4 to 5 times, larger than the opening angle ofthe second virtual cone.

The centering recess is preferably embodied on the same component as theabove-described cylindrical bearing surfaces that interact with thenon-locating bearing. A bearing stem connected directly to the workingapparatus, such as the one already described above, can serve as such acomponent. In order to ensure that a bearing stem has sufficient loadcapacity in consideration of the large working forces occurring duringearth working and the reaction forces resulting therefrom, the openingangle of the first virtual cone is preferably larger than the openingangle of the above-described first notional cone. Alternatively, orpreferably additionally, the opening angle of the second virtual conecan be smaller than the opening angle of the above-described secondnotional cone. It is thereby possible to furnish a bearing stem, havingan axially continuous recess, which has over its axial extent a materialthickness that is always radially sufficient but not excessive.

A preferred displacement of the working apparatus into the operatingposition by means of a pivoting movement of the encasing component isdescribed below. With this type of displacement of the working apparatusinto the operating position, both sliding of the non-locating bearingonto the bearing stem and sliding of the centering recess onto thecentering stem occur with a close correlation in time, and act both onthe non-locating bearing and on the working apparatus solely by thepivoting of the encasing component constituting the only force transferoperation from outside. There is therefore a close technical correlationbetween the external conformation of the bearing stem and the internalconformation of the centering recess, which constitute the conformationsinvolved in a unified displacement operation.

Additionally or alternatively, simplified loading of the centering steminto the centering recess, and subsequent displacement of the workingapparatus into the operating position, can also be achieved by the factthat the pre-centering recess portion is embodied to be longer than themain centering recess portion. Also preferably, the magnitude by whichthe main centering recess portion is axially longer than thepre-centering recess portion can be greater than the magnitude by whichthe main centering recess portion is located radially farther outwardthan the pre-centering recess portion. Also preferably, the axialspacing between the main centering recess portion and the pre-centeringrecess portion can be smaller than their radial spacing from oneanother. This makes possible the advantageous use of axially shortercentering stems. For clarification, be it noted that any bevels orfillets or the like that may be present at one axial end of both themain centering recess portion and the pre-centering recess portion arenot part of the relevant centering recess portion.

It is thus also possible, in the context of installation on the driveconfiguration, for example upon placement of a new or repaired workingapparatus on the machine body, to preposition the working apparatus,having the counterpart centering configuration rigidly connected to it,approximately axially on the drive configuration, and to displace it bymeans of the central bolt arrangement into its final axial position andretain it there. The axial displacement of the working apparatus can beaccomplished by direct engagement of a torque tool on the boltcomponent, for example using a torque wrench, a wrench, or an impactdriver and the like, so that the bolt arrangement, but not a drive motoror rotational drive permanently or temporarily coupled to the driveconfiguration, is used for axial positioning of the working apparatusrelative to the drive configuration. The advantage is that upon a toolengagement on the bolt component, the latter can be brought helicallycloser to the drive configuration without resulting in a rotationalmovement of the drive formation and therefore also of the workingapparatus. A substantially lower torque than the torque recited abovefor establishing and/or releasing axial positional retention issufficient for this. With a corresponding embodiment of the boltingmoment bracing configuration and counterpart bracing region, the workingapparatus can be displaced axially by means of the bolt arrangement,using the bolting moment bracing configuration and the counterpartbracing region, from a preparation position axially remote from theoperating position toward the operating position or, even moreadvantageously, into the operating position. The possible source ofdrive force recited above can once again be used for this. The boltingmoment bracing configuration is, for this purpose, preferablyarrangeable on the bolt component of the bolt arrangement latchably orotherwise with elevated axial pull-off resistance, so that the boltingmoment bracing configuration remains in engagement with the boltcomponent during the process of bolting it on.

When the working apparatus has reached its intended axial position, theaforementioned method and the aforementioned bolting moment bracingarrangement can be used to exert the desired high tightening torque onthe bolt arrangement by driving the drive configuration.

For axial sliding of the drive apparatus onto the drive configuration,it is sufficient if the bolt component encompasses a portion that comesdirectly into abutment against a component connected rigidly to theworking apparatus or against an auxiliary component that transfers aforce from the bolt component to the working apparatus. It is sufficientfor this purpose if the portion of the bolt component projects radiallybeyond a central opening, penetrated by the bolt arrangement, of thecomponent rigidly connected to the working apparatus or of the auxiliarycomponent. The auxiliary component can be a sleeve, if applicable aconical sleeve.

In principle, as already indicated above, the bolt component can be anut and the drive configuration can encompass a threaded shank, standingout from the drive configuration in a direction away from the driveaxial end toward the retention axial end, onto which the nut is screwed.This is not preferred, however, since upon installation of the workingapparatus onto the drive configuration and deinstallation therefrom, theworking apparatus (which as a rule is heavy) can come into contact withthe threaded shank and deform it. Provision is therefore made that thebolt component comprises a threaded shank and a tool engagement portion,radially wider compared with the threaded shank, having a toolengagement configuration, the shank being boltable into the driveconfiguration, in particular into the centering configuration.

The bolt component is preferably a bolt having a threaded shank and ahead embodied in one piece thereon. The bolt component is then the boltarrangement. The tool engagement configuration is identical to the onerecited above, which can be brought into engagement with the engagementportion of the bolting moment bracing arrangement embodied separatelyfrom the bolt arrangement or bolt component.

Alternatively, the working apparatus can also be displaced from thepreparation position toward the operating position without using thebolt component. This is because when the non-locating bearing forrotational mounting of the working apparatus is arranged on the machineframe pivotably movably together with an encasing component, asdescribed above, the working apparatus can be displaced, by a pivotingmovement of the encasing component from the access position into theclosed position, from the preparation position toward the operatingposition, particularly preferably into the operating position.

In order to assist the displacement of the working apparatus from thepreparation position toward the operating position, preferably into theoperating position, the encasing component can be drivable by a pivotactuator for the pivoting movement at least during a movement segmentfrom the access position into the closed position. The encasingcomponent can also be drivable by the pivot actuator, bidirectionally inboth opposite pivot directions, for the pivoting movement between theaccess position and closed position.

For example, the encasing component can be moved manually from theaccess position toward the closed position until a portion of thenon-locating bearing comes into abutting engagement with a portion ofthe bearing stem. Once this abutting engagement is established, theencasing component can be moved into the closed position by impingementof force by a pivot actuator, for example by one or severalpiston/cylinder arrangements, the working apparatus simultaneously beingdisplaced into the operating position and the non-locating bearing inthat context being slid onto the bearing stem into a position ready forrotational mounting.

The working apparatus can also be moved in simple fashion out of itsoperational axial position after axial positioning retention isreleased. Particular attention is to be paid in this context to aninitial movement introducing the axial pulling-off movement, since theworking apparatus, not only heavily mechanically loaded but also greatlyimpacted by dirt, often gets stuck in its axial operating position onthe drive configuration specifically during earth-removing operation,and the elevated adhesion thereby brought about must first be overcome.These holding forces, which are in fact undesired, can be overcome inmechanical fashion after axial positioning retention release by the factthat a centering component, comprising the counterpart centeringconfiguration or connected rigidly to the counterpart centeringconfiguration, comprises a central passage through which the driveconfiguration, in particular the centering configuration, is accessiblewhen the working apparatus is arranged on the drive configuration. Thecentering component furthermore comprises, with an axial spacing in adirection away from the drive configuration, a fastening and/oradvancing configuration in particular in the form of a thread, in whicha release component is fastenable after the bolt component is removedfrom the earth working machine (once again with the working apparatusarranged on the drive configuration), and/or with which the releasecomponent is advanceable toward the drive configuration, in particulartoward the centering configuration, with axial force bracing against thecentering component.

According to a preferred refinement of the present invention, thecentering component can be the aforementioned bearing stem of theworking apparatus which interacts with the non-locating bearing forrotational mounting of the working apparatus, or can comprise thatbearing stem.

In accordance with an approach that is preferred in design terms becauseof its stability, the release component can comprise: a cooperatingconfiguration for engagement with the fastening and/or advancingconfiguration; an abutment portion for exerting axial force on the driveconfiguration, in particular on the centering configuration; and atorque-transferring configuration for torque-transferring engagementwith a torque tool. The torque tool can be a manual or automated torquewrench, or can be the bolting moment bracing arrangement. The engagementregion of the bolting moment bracing arrangement can be brought intotorque-transferring engagement with the torque-transferringconfiguration. The abutment portion of the release component can then bebrought into abutment against the drive configuration, with torquebracing of the release component by way of the bolting moment bracingarrangement on the one side of the earth working machine, and byintroducing a torque on the axially opposite other side (drive side) ofthe earth working machine utilizing the engagement between thecooperating configuration and the fastening and/or advancingconfiguration. As torque introduction continues, the working apparatuscan then be pushed axially off the drive configuration by way of therelease component that abuts against the drive configuration and is inpositive engagement with the working apparatus. This is because thepositive engagement, preferably e.g. a bolting engagement, enables anaxial relative movement between the working apparatus and releasecomponent. This aspect of the use of the bolting moment bracingarrangement on an earth working machine, together with the releasecomponent on a working apparatus that radially externally surrounds thedrive configuration and is no longer retained on the drive configurationin terms of its axial relative position, is not only a preferredrefinement of the above inventive idea of using the bolting momentbracing arrangement together with the bolt arrangement, but alsoconstitutes a further inventive idea independent of the one above. Thisis because in principle the release component also constitutes a,preferably likewise central, bolt arrangement within the meaning of thepresent invention, with the difference that it is embodied not to retainthe working apparatus on the drive configuration against axialdisplacement but for exactly the opposite purpose: for axialdisplacement of the working apparatus relative to the driveconfiguration away from the latter.

Preferably the cooperating configuration is an external thread and thefastening or advancing configuration is an internal thread. Alsopreferably, the central passage of the centering component has a largerunobstructed width than a central recess of the drive configuration orcentering configuration in which a threaded portion of the boltarrangement is received when axial positional retention is established.In this case a shank portion which is stable, because it is sufficientlythick, and at whose longitudinal end located remotely from thecooperating configuration the abutment portion is located, can protrudefrom the cooperating configuration. This can be brought, by advancingthe releasing component, preferably by helical advance, into abutmentwith the material surrounding the central recess of the driveconfiguration, in particular of the centering configuration. Thetorque-transferring configuration can be embodied on that side of thecooperating configuration which faces away from the abutment portion.

The working apparatus is preferably a milling drum or milling rotorencompassing a milling drum tube which is radially internally hollow atleast in portions and on whose radially outward-facing sidematerial-removing tools, such as milling bits and, for simplifiedreplacement thereof, bit holders and/or quick-change bit holders, can bearranged in a manner known per se. The working apparatus can be capableof being lowered toward the contact substrate and raised away from it,relative to the machine body or together with the machine frame carryingthe machine body.

In earth working machines having milling drums, the one side of theearth working machine that is located closer to the drive axial end ofthe milling drum mounted operationally on the machine body is usuallythe drive side, and the opposite side of the earth working machine whichis located closer to the retention axial end of the milling drum is theso-called “idle” side. Particularly advantageously, the presentinvention makes it possible to establish or release axial positionalretention of the working apparatus on the drive configuration by boltingmoment bracing of the central bolt arrangement on the idle side, and byintroducing drive torque into the drive configuration on the drive side,of the earth working machine.

The present invention likewise makes it possible, additionally oralternatively, to mechanically push the working apparatus in an axialdirection away from the drive configuration utilizing the aforementionedrelease component and the bolting moment bracing arrangement. Boltingmoment bracing of the release component on the idle side is effected bythe bolting moment bracing arrangement, and an introduction of drivetorque into the drive configuration is accomplished on the drive side ofthe earth working machine.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be explained in further detail below withreference to the appended drawings, in which:

FIG. 1 is a schematic side view of an embodiment according to thepresent invention of an earth working machine in the form of a largemilling machine, in a position for rolling travel operation;

FIG. 2 is a schematic longitudinal section view through the workingapparatus of the earth working machine of FIG. 1 in an operational statefor earth working, in which the section plane contains the rotation axisof the working apparatus;

FIG. 3 is an enlarged partial longitudinal section view of the right (inFIG. 2) longitudinal end of the drive configuration and workingapparatus;

FIG. 4 is a perspective view of a bolting moment bracing arrangement forestablishing and/or releasing axial positional retention of the millingdrum on a drive configuration of the earth working machine;

FIG. 5 shows, in isolation, the bolting moment bracing arrangement ofFIG. 4 embodied as a tool arrangement;

FIG. 6 is a partial longitudinal section view, corresponding in terms ofessential constituents to FIG. 3, of the right longitudinal end regionof the drive configuration and milling drum, having a bolting momentbracing arrangement according to FIGS. 4 and 5 arranged on the boltarrangement;

FIG. 7 is a longitudinal section view, corresponding to the view of FIG.6, of an alternative embodiment of the drive configuration and millingdrum;

FIG. 8 shows a drive configuration and milling drum, correspondingsubstantially to the embodiments of FIGS. 3 and 6, having a releasecomponent for pulling the milling drum axially off the driveconfiguration;

FIG. 9 shows the release component of FIG. 8 in isolation;

FIG. 10 shows a third embodiment of the drive configuration and millingdrum in a partial longitudinal section view corresponding to FIGS. 3 and6 to 8;

FIG. 11A is a side view of a preferred bearing component encompassing aconnecting flange and a bearing stem, protruding therefrom, as shown inFIG. 6;

FIG. 11B is a longitudinal section view of the bearing component of FIG.11A;

FIG. 12 is a plan view of the bearing component of FIGS. 11A and 11B;

FIG. 13A is a side view of a bearing component alternative to the one ofFIG. 11A;

FIG. 13B is a longitudinal section view of the bearing component of FIG.13A; and

FIG. 14 is a plan view of the bearing component of FIG. 14.

DETAILED DESCRIPTION

In FIG. 1, an embodiment according to the present invention of an earthworking machine in the form of a ground milling or road milling machineis labeled 10 in general. It encompasses a machine frame 12 thatconstitutes the basic framework for a machine body 13. Machine body 13encompasses machine frame 12 and the components of machine 10 which areconnected to the machine frame and are optionally movable relativethereto.

Machine body 13 encompasses front lifting columns 14 and rear liftingcolumns 16, which are connected at one end to machine frame 12 and atthe other end respectively to front drive units 18 and to rear driveunits 20. The distance of machine frame 12 from drive units 18 and 20 ismodifiable by way of lifting columns 14 and 16.

Drive units 18 and 20 are depicted by way of example as crawler trackunits. In a departure therefrom, individual, or all, drive units 18and/or 20 can also be wheel drive units.

The viewer of FIG. 1 is looking toward the earth working machine (orsimply “machine”) 10 in transverse machine direction Q that isorthogonal to the drawing plane of FIG. 1. A longitudinal machinedirection orthogonal to transverse machine direction Q is labeled L andextends parallel to the drawing plane of FIG. 1. A vertical machinedirection H likewise extends parallel to the drawing plane of FIG. 1 andorthogonally to longitudinal and transverse machine directions L and Q.The arrowhead of longitudinal machine direction L in FIG. 1 points in aforward direction. Vertical machine direction H extends parallel to theyaw axis of machine 10, longitudinal machine direction L extendsparallel to the roll axis, and transverse machine direction Q extendsparallel to pitch axis Ni.

Earth working machine 10 can comprise an operator's platform 24 fromwhich a machine operator can control machine 10 via a control panel 26.

Arranged below machine frame 12 is a working assembly 28, hereconstituting, for example, a milling assembly 28 having a milling drum32, received in a milling drum housing 30, that is rotatable around amilling axis R extending in transverse machine direction Q so thatsubstrate material can be removed therewith during an earth workingoperation, starting from contact surface AO of substrate U to a millingdepth determined by the relative vertical position of machine frame 12.Milling drum 32 is therefore a working apparatus within the meaning ofthe present Application.

The vertical adjustability of machine frame 12 by way of lifting columns14 and 16 also serves to set the milling depth, or generally workingdepth, of machine 10 in the context of earth working. Earth workingmachine 10 depicted by way of example is a large milling machine, forwhich the placement of milling assembly 28 between the front and reardrive units 18 and 20 in longitudinal machine direction L is typical.Large milling machines of this kind, or indeed earth-removing machinesin general, usually comprise a transport belt so that removed earthmaterial can be transported away from machine 10. In the interest ofbetter clarity, a transport belt that is also present in principle inthe case of machine 10 is not depicted in FIG. 1.

It is not apparent from the side view of FIG. 1 that machine 10comprises, in both its front end region and its rear end region, tworespective lifting columns 14 and 16 each having a drive unit 18, 20connected to it. Front lifting columns 14 are respectively connected todrive units 18, in a manner also known per se, by means of a drive unitconnecting structure 34, for example a connecting fork fitting arounddrive unit 18 in transverse machine direction Q. Rear lifting columns 16are connected to their respective drive unit 20 via a drive unitconnecting structure 36 constructed identically to drive unit connectingstructure 34. Drive units 18 and 20 are of substantially identicalconstruction, and constitute propelling unit 22 of the machine. Driveunits 18 and 20 are motor-driven, as a rule by a hydraulic motor (notdepicted).

The drive energy source of machine 10 is constituted by an internalcombustion engine 39 received on machine frame 12. In the exemplifyingembodiment depicted, milling drum 32 is rotationally driven by it. Theoutput of internal combustion engine 39 furthermore makes available onmachine 10 a hydraulic pressure reservoir by means of which hydraulicmotors and hydraulic actuators on the machine can be operated. Internalcombustion engine 39 is thus also a source of the propulsive power ofmachine 10.

In the example depicted, drive unit 18, having a travel directionindicated by double arrow D, comprises a radially internal receiving andguidance structure 38 on which a circulating drive track 40 is arrangedand is guided for circulating movement.

Lifting column 14, and with it drive unit 18, is rotatable around asteering axis S by means of a steering apparatus (not further depicted).Preferably additionally, but also alternatively, lifting column 16, andwith it drive unit 20, can be rotatable by means of a steering apparatusaround a steering axis parallel to steering axis S.

FIG. 2 is a longitudinal section view of milling drum 32 of FIG. 1 in asection plane containing rotation axis R of the milling drum.

Milling drum 32 encompasses a substantially cylindrical milling drumtube 42 on whose radially outer side bit holders or quick-change bitholders, having milling bits in turn received replaceably therein, areprovided in a manner known per se. A dot-dash line 44 indicates theeffective diameter (cutting cylinder) of milling drum 32, defined by themilling bit tips of the milling bits (not depicted). Milling drum 32 isin an operational condition ready for earth-removing work. Milling drum32 is connected for that purpose in torque-transferring fashion to adrive configuration 46. Milling drum 32 radially externally surroundsdrive configuration 46.

A planetary gearset that steps speed down and steps torque up isreceived in a transmission housing 52. A right (in FIG. 2) part 52 a oftransmission housing 52 is coupled to the ring gear of the planetarygearset for rotation together. A left (in FIG. 2) part 52 b oftransmission housing 52 is a machine frame-mounted part of machine body13.

Drive configuration 46 encompasses an internal tube 48, a support cone50, and part 52 a, rotatable relative to machine frame 12, oftransmission housing 52. Support cone 50 and internal tube 48 areconnected to one another, and are connected as an assembly totransmission housing part 52 a for rotation together around drive axis Aof drive configuration 46. With milling drum 32 in the operationalstate, drive axis A of drive configuration 46 and rotation axis R ofmilling drum 32 are coaxial.

Milling drum tube 42 is braced against support cone 50 of driveconfiguration 46 by a negatively conical counterpart support cone 51.

Drive configuration 46 is furthermore connected to a drivetorque-transferring arrangement 54 that, in the example depicted,encompasses inter alia a belt pulley 55. Belt pulley 55 is connected toan input shaft (not depicted in FIG. 2) of the planetary gearset intransmission housing 52. The input shaft, connected to belt pulley 55for rotation together, extends through a shaft tunnel 56 that is machineframe-mounted in the exemplifying embodiment depicted and is rigidlyconnected to transmission housing part 52 b.

Drive configuration 46 forms, with the machine frame-mounted assemblymade up of transmission housing part 52 b and shaft tunnel 56, a driveassembly 47 that projects axially into milling drum 32 from a driveaxial end 32 a of milling drum 32. Milling drum 32 preferably protrudesaxially on both sides beyond drive configuration 46, constituting thatpart of drive assembly 47 which is rotatable relative to machine frame12.

Drive assembly 47, and with it drive configuration 46, is mounted onmachine body 13 in the region of shaft tunnel 56. The mounting of driveconfiguration 46 in the region of the rotatable transmission housingpart 52 a constitutes a locating bearing of drive configuration 46.Axial longitudinal end 46 a, located closer to belt pulley 55, of driveconfiguration 46 is therefore also referred to as the “locatingbearing-side” longitudinal end 46 a.

Milling drum 32 extends axially, along its rotation axis (milling axis)R that coincides with drive axis A in the operational state, betweendrive axial end 32 a located closer to drive torque-transferringarrangement 54 in FIG. 2 and a retention axial end 32 b, locatedoppositely from the drive axial end, that is located closer to the axialpositional retention point of milling drum 32 in the operational state.

At non-locating bearing-side longitudinal end 46 b located axiallyoppositely from locating bearing-side longitudinal end 46 a, driveconfiguration 46 comprises a support ring 58 and an end-located cover 60connected to support ring 58. In the exemplifying embodiment depicted,support ring 58 is connected to internal tube 48 by welding. Cover 60can likewise be welded, or also bolted, onto support ring 58. It isconnected to support ring 58 and to internal tube 48 for rotationtogether around drive axis A.

Support ring 58 can be embodied in a variety of ways. Its conformationis not of essential importance. In the depictions of the presentApplication it is shown in a slightly differing form in each case, butthis has no influence at all on the present invention.

The same is true of the radially external regions of cover 60 whichinteract with support ring 58 to constitute a nonrotatable connection.

In the first exemplifying embodiment depicted in FIG. 2, a hydrauliccylinder 62, which is arranged with its hydraulic cylinder axis coaxialwith drive axis A of drive configuration 46, is received in interior 49of drive configuration 46. Hydraulic cylinder 62 can be supplied withhydraulic fluid by means of a hydraulic connector line 64 through anenergy passthrough opening 66 in cover 60.

Hydraulic connector line 64 ends, at its longitudinal end locatedremotely from hydraulic cylinder 62, in a coupling configuration 68 thatis connectable, in order to supply hydraulic cylinder 62, to acounterpart coupling configuration of a supply line (not depicted) sothat piston rod 63 can be extended from hydraulic cylinder 62 andretracted back into it. Two hydraulic connector lines 64 can be providedin order to operate a preferred double-acting hydraulic cylinder, onefor each movement direction of piston rod 63.

Once axial positional retention, as shown in FIG. 2, of milling drum 32on drive configuration 46 has been released, milling drum 32 can beaxially pushed away from drive configuration 46 for deinstallation usingpiston rod 63, or pulled onto drive configuration 46 for installation.

A connecting ring 70 is arranged radially internally on milling drumtube 42 in a region located closer to retention axial end 32 b, and isconnected, by way of a welded join in the example depicted, to millingdrum tube 42 for rotation together.

Milling drum tube 42 is rigidly connected to a connecting flange 74 viaa connecting ring 70 by means of threaded studs 72.

Provided on connecting flange 74, preferably in one piece therewith, isa bearing stem 74 a that protrudes axially toward retention axial end 32b from a connecting region of connecting flange 74 with connecting tube70.

With milling drum 32 in the operational state, a non-locating bearing 76that braces drive configuration 46 is arranged on bearing stem 74 a.Non-locating bearing 76, arranged at an axial distance from the locatingbearing, can be pulled off axially from bearing stem 74 a.

Non-locating bearing 76 can be received, for example, in a side plate orside door 30 a (see FIGS. 3, 4, 6, 7, and 10) that is part of millingdrum housing 30 and is end-located axially oppositely from milling drum32 at retention axial end 32 b. All that is shown in FIG. 2 is acomponent 30 b, rigidly connected to such a side wall 30 a, constitutinga bearing surface for the outer bearing ring of non-locating bearing 76.

Side wall 30 a, constituting side door 30 a, is preferably providedpivotably on machine frame 12 so that drive configuration 46 and/ormilling drum 32 in the interior of milling drum housing 28 can be madeaccessible by simply pivoting open and closed. Side door 30 a ispreferably pivotable around a pivot axis parallel to vertical machinedirection H, since the pivoting of side door 30 a then does not need tooccur against gravity in any pivoting direction. Non-locating bearing76, constituting non-locating assembly 85, is preferably mounted on sidedoor 30 a together with auxiliary component 86 (explained below) in sucha way that the non-locating bearing, in particular constitutingnon-locating bearing assembly 85, is pivotable together with side door30 a. Opening side door 30 a causes non-locating bearing 76, inparticular non-locating bearing assembly 85, to be pulled axially offthe bearing stem mounted by non-locating bearing 76. As is preferred,this can be bearing stem 74 a that is connected to connecting flange 74.It can also be bearing stem (centering stem) 160 a, described below inconjunction with the second exemplifying embodiment shown in FIG. 7,which protrudes axially from cover 160 of drive configuration 146 andpasses through connecting flange 174.

Also preferably, the distance of the side door pivot axis from side door30 a is greater than the radius of the cutting cylinder, shown in FIG.2, of milling drum 32, so that the circular path of non-locating bearing76 or of non-locating bearing assembly 85 when pivoting together withside door 30 a has the largest possible radius and thus the leastpossible curvature. This makes it easier to pull non-locating bearing76, in particular non-locating bearing assembly 85, off the bearing stemthat mounts milling drum 32 for rotation around its rotation axis R, orto pull it onto said bearing stem.

As will be explained in more detail with reference to the enlargeddepiction in FIG. 3 of functional longitudinal end 46 b of the driveconfiguration, milling drum 32 is retained in its axial position ondrive configuration 46 only by a single central retaining bolt 78.Retaining bolt 78 constitutes a bolt arrangement of the presentApplication.

Milling drum 32 is thus braced on drive configuration 46, coaxially withdrive axis A, against counterpart support cone 51 and against connectingflange 74.

In FIG. 3, support ring 58, cover 60, and connecting flange 74 haveconformations that deviate slightly from what is depicted in FIG. 2. Theconformations of the aforesaid components do not, however, differsufficiently from what is depicted in FIG. 2 for those differences tohave an influence on the implementation of the present invention.

Hydraulic cylinder 62, with its piston rod 63, is omitted from FIG. 3 inthe interest of clarity. Threaded studs 72 for connecting connectingflange 74 to connecting ring 70 are also not depicted in the interest ofclarity.

Embodied on cover 60, preferably in one piece therewith, is a centeringconfiguration 60 a in the form of a centering stem which protrudes fromcover 60, in a direction away from the locating bearing-sidelongitudinal end of drive configuration 46, toward retention axial end32 b of milling drum 32. Centering stem 60 a projects into a counterpartcentering configuration 74 b, embodied as a centering recess, onconnecting flange 74, and thereby centers milling drum tube 42,connected rigidly to connecting flange 74, with respect to drive axis A.Connecting flange 74 is therefore a centering component recited in theintroductory part of the description. Cover 60 comprises a centralrecess 60 b, passing axially through it, through which piston rod 63 inFIG. 2 and FIG. 3 can pass axially.

At the end region facing toward retention axial end 32 b of centeringstem 60 a, recess 60 b in centering stem 60 a is equipped with aninternal thread into which the central retaining bolt 78 is threaded.

Although the bolt arrangement can also be embodied in several parts, forexample by way of a threaded rod and a retaining nut optionally with awasher, rather than as a one-piece retaining bolt 78, the one-piece boltarrangement in the form shown in FIG. 3 is preferred because of itssimple and reliable handling and stowing capability. The centralretaining bolt 78 encompasses a threaded shank 78 a having an externalthread, and a bolt head 78 b projecting radially beyond threaded shank78 a and having a tool engagement configuration 78 c known per se, forexample in the form of a hex head polyhedron. Embodied between threadedshank 78 a and tool engagement configuration 78 c is an abutment portion78 d constituting an axially narrow but radially protruding cylinder.This abutment portion 78 d is embodied in the present example in onepiece with threaded shank 78 a and tool engagement configuration 78 c,but alternatively can also be provided as a separate washer.

Bolt head 78 b thus clamps bearing stem 74 a, and with it connectingflange 74 and with that in turn connecting ring 70 and milling drum tube42, axially against support cone 50 of drive configuration 46.

When milling drum 32 is arranged axially at a distance from itsoperating position but still with a certain prepositioning, for examplesuch that that longitudinal end of centering stem 60 a which is locatedremotely from support ring 58 is already projecting into centeringrecess 74 b of connecting flange 74, it is thus possible to move millingdrum 32 with centering bolt 78 axially into its operating position. Caremust simply be taken that pins 80 provided on cover 60 at a radialdistance from drive axis A can travel into recesses 74 c, provided forthat purpose, of connecting flange 74, so as thereby to couple cover 60to connecting flange 74 in order to transfer torque between driveconfiguration 46 and milling drum 32.

Axially “pulling” or clamping milling drum 32 onto drive configuration46 by means of retaining bolt 78 requires only a comparatively low levelof torque that can be introduced via tool engagement configuration 78 cinto retaining bolt 78 using conventional torque wrenches or alsomechanized torque wrenches.

As an alternative to pulling or clamping milling drum 32 onto driveconfiguration 46 by means of retaining bolt 78, milling drum 32 can alsobe slid through the pivotable side door 30 a onto drive configuration46. During this sliding-on operation, not only is counterpart centeringconfiguration 74 b slid onto centering stem 60 a, but non-locatingbearing 76, in particular non-locating bearing assembly 85, ispreferably also slid onto bearing stem 74 a.

In order to facilitate the conveying, mentioned in the precedingparagraph, of milling drum 32 into an operational position simply bypivoting side door 30 a into its closed position shown in FIGS. 3, 6, 7,and 10 in which it closes off milling drum housing 30, earth workingmachine 10 preferably comprises an actuator that assists the pivoting ofside door 30 a at least in a movement direction, and at least in amovement region containing the closed position. Particularly preferably,this is a final movement region in the context of the movement of sidedoor 30 a into the closed position. The force needed in order to slidemilling drum 32 onto drive configuration 46, and also the force neededto slide non-locating bearing 76 or non-locating bearing assembly 85onto bearing stem 74 a, can thus be applied entirely or at least partlyby the actuator. Such an actuator can comprise, for example, one orseveral piston/cylinder arrangements. The cylinder is preferablypivot-mounted on machine frame 12. When side door 30 a has been broughtsufficiently close to an engagement configuration of the piston rod andwhen the piston rod is extended, side door 30 a can be brought intoengagement with the engagement configuration of the piston rod,preferably into a positive engagement transferring a particularly largeamount of force, so that the one or several piston/cylinder arrangementscan then at least assist, preferably independently execute, theremainder of the closing movement of side door 30 a.

Preferably the actuator can also assist or in fact execute the pivotingmovement of side door 30 a, together with non-locating bearing 76 orwith non-locating bearing assembly 85, in an initial movement region ofthe pivoting movement of side door 30 a out of the closed positiontoward the access position, non-locating bearing 76, in particularnon-locating bearing assembly 85, being pulled off bearing stem 74 aover that region. The actuator can also be an electromechanicalactuator.

A retaining moment for axial positional retention of milling drum 32 ondrive configuration 46 by way of retaining bolt 78 is, however, ordersof magnitude greater. This is introduced into retaining bolt 78, inaccordance with the present invention, as depicted in FIG. 4.

FIGS. 4 and 5 depict a bolting moment bracing arrangement 82 used toestablish and release axial positional retention of milling drum 32 ondrive configuration 46. Bolting moment bracing arrangement 82 extendsalong a component axis SA that is coaxial with drive axis A when boltingmoment bracing arrangement is placed onto retaining bolt 78.

Bolting moment bracing arrangement 82 is embodied as a fitover toolhaving an engagement region 82 a (see FIG. 5) that is embodied, in theexample depicted, as a recess having a shape complementary to toolengagement configuration 78 c of retaining bolt 78, i.e. in this case asa hex socket polyhedron. Bolting moment bracing arrangement 82 can thusbe placed axially, with its engagement region 82 a, onto bolt head 78 bof retaining bolt 78. A torque can thus be transferred in positivelyengaging fashion between bolt 78 and bolting moment bracing arrangement82.

Tool engagement configuration 78 c of retaining bolt 78 thus constitutesa counterpart engagement region of engagement region 82 a.

Engagement region 82 a is provided on an engagement portion 82 b ofbolting moment bracing arrangement 82. Two projections 82 c and 82 d,for example, project from that engagement portion 82 b radially (withreference to component axis SA) in diametrical opposition.

With bolting moment bracing arrangement 82 in the state, shown in FIG.4, of being placed onto the central retaining bolt 78, bolting momentbracing arrangement 82 is radially externally surrounded by acounterpart bracing component 84 that is fixedly connected to side plate30 a of milling drum housing 30, for example by bolting. In theexemplifying embodiment depicted, counterpart bracing component 84 isarranged permanently on side plate 30 a.

Counterpart bracing component 84 comprises a central recess 84 a throughwhich head 78 b of retaining bolt 78 is axially accessible externally,i.e. from outside machine body 13, in order to place bolting momentbracing arrangement 82 thereonto and pull it off therefrom.

Recess 84 a is (slightly) radially and (substantially) circumferentiallylarger than the corresponding respective radial and circumferentialdimensions of engagement portion 82 b having projections 82 c and 82 d.As a result, bolting moment bracing arrangement 82 can always be placedonto the retaining bolt regardless of the current rotational position ofretaining bolt 78 that co-rotates with milling drum 32 during operation.Because, in the case of a hex head tool engagement configuration, theindividual flat surfaces of tool engagement configuration are eachrotated 60° with respect to their closest engagement surface in acircumferential direction, recess 84 a preferably extends over at least60° in the circumferential region that accommodates projections 82 c and82 d.

Surfaces 82 e, facing in a circumferential direction, of projection 82c, and surfaces 82 f, facing in a circumferential direction, ofprojection 82 d form bracing regions of bolting moment bracingarrangement 82; of these, surfaces 82 e can come into abutment againstflanks 84 b and surfaces 82 f can come into abutment against flanks 84c, which delimit in a circumferential direction those regions of recess84 a in which projections 82 c and 82 d are received when bolting momentbracing arrangement 82 is in place. The two flanks 84 b facing in acircumferential direction, and the two flanks 84 c facing in acircumferential direction, of recess 84 a thus form counterpart bracingregions of counterpart bracing component 84.

It is thus possible, as necessary, to place bolting moment bracingarrangement 82 axially onto bolt head 78 without further preparatoryhandling, and to cause drive configuration 46 to rotate around driveaxis A. This can occur either by way of internal combustion engine 39and drive torque-transferring arrangement 54, or by way of a rotationaldrive (not depicted in the Figures) that can be coupled via couplingconfiguration 57 onto belt pulley 55 and thus indirectly onto driveconfiguration 46 for torque transfer. Merely for the sake ofcompleteness, be it noted that coupling configuration 57 can be providedat any point on drive torque-transferring arrangement 54, so long as thedrive configuration can be caused to rotate around drive axis A byactuating coupling configuration 57. The rotational drive that can becoupled to coupling configuration 57 can also be a manual rotationaldrive.

Thanks to the planetary gearset arranged between drivetorque-transferring arrangement 54 or coupling configuration 57 on theone hand, and cover 60 or its centering stem 60 a in transmissionhousing 52 on the other hand, because of the large torque step-up ratioof the planetary gearset a torque of more than 2500 Nm or even more than3000 Nm can be achieved with a comparatively low input-side torque, forexample in the range from 250 to 300 Nm, at centering stem 60 a thatcarries the internal thread for retaining bolt 78.

After bolting moment bracing arrangement 82 is placed onto retainingbolt 78, a rotation of drive configuration 46 causes flanks 82 e and 82f to come into abutment, depending on the direction of the rotationalmovement of drive configuration 46, against flanks 84 b, 84 c, facing ina circumferential direction, of recess 84 a of counterpart bracingcomponent 84. As a result of the positive engagement of engagementregion 82 a with bolt head 78 b of the retaining bolt, a drive torqueintroduced into drive configuration 46 on the locating-bearing side ofdrive configuration 46 is braced by positively engaging abutment betweenprojections 82 c and 82 d and counterpart bracing component 84 on thenon-locating-bearing side of drive configuration 46. This ensures thatas rotational driving of drive configuration 46 continues, a relativerotation occurs between retaining bolt 78 and drive configuration 46,and a helical movement of retaining bolt 78 relative to driveconfiguration 46 (in the example depicted, relative to centering stem 60a) thus occurs. Retaining bolt 78 can thus be tightened or loosened withan extremely high torque as a result of the bracing effect of boltingmoment bracing arrangement 82 in interaction with counterpart bracingcomponent 84.

Axial positional retention of milling drum 32 relative to driveconfiguration 46 can be established and released without tools with theexception of bolting moment bracing arrangement 82.

Counterpart bracing component 84 can remain permanently on machine body13, more precisely on the end-located side wall 30 a of milling drumhousing 30.

FIG. 4 is a view of the so-called “idle” side of earth working machine10, i.e. that side of machine 10 which faces away from the viewer inFIG. 1. In FIG. 1 the viewer is looking at the oppositely locatedso-called “drive” side of machine 10. With machine 10 in the operationalstate, drive axial end 32 a of milling drum 32 is located closer to thedrive side of machine 10, and retention axial end 32 is closer to theidle side. The idle side of earth working machine 10 is usually theright side in a forward travel direction.

Once axial positional retention has been established, driveconfiguration 46 can be driven a little way in the opposite rotationdirection in order to release the abutment between flanks 82 e, 82 f ofprojections 82 c and 82 d of bolting moment bracing arrangement 82 andflanks 84 b, 84 c of counterpart bracing component 84, so that boltingmoment bracing arrangement 82 can be manually pulled off axially fromretaining bolt 78 with little force.

In FIG. 5, dashed line 83 shows a possible physical separation betweenengagement portion 82 b comprising projections 82 c and 82 d, and aradially inner core portion 82 g comprising engagement region 82 a.Engagement portion 82 b and core portion 82 g can be connected by a testapparatus, concealed by the aforesaid portions, that is embodied toallow a torque that is transferred between engagement portion 82 b andcore portion 82 g to be capable of being checked. For example, the testapparatus can be a slip coupling that permits a torque transfer betweenengagement portion 82 b and core portion 82 g only up to a predeterminedlimit torque or a limit torque predeterminable by an adjustment action,and/or the test apparatus can output a signal, for example a sound, forexample a click that is known from mechanical torque wrenches, when thelimit torque is reached.

The bolting moment bracing arrangement can, however, also be embodied inone piece.

FIG. 6 depicts what is shown in FIGS. 2 and 3, with bolting momentbracing arrangement 82 placed onto bolt head 78 b. Bolting momentbracing arrangement 82 is not sectioned.

Projection 82 d extends orthogonally to the drawing plane of FIG. 6toward the viewer. Projection 82 c is located behind the drawing planein FIG. 6 and is concealed by engagement portion 82 b. The counterpartbracing component is not shown in FIG. 6.

FIG. 7 shows a second embodiment of working assembly 28.

Components and component portions identical and functionally identicalto those in the first embodiment are labeled in the second embodimentwith the same reference characters but incremented by 100. The secondembodiment of FIG. 7 is explained below only insofar as it differs fromthe first embodiment to an extent essential in terms of the invention.

An essential modification of the second embodiment as compared with thepreviously described first embodiment is the conformation of centeringstem 160 a, which both acts as a centering configuration with respect toconnecting flange 174 of milling drum 132 and serves as a bearing stemwith respect to non-locating bearing 176.

Counterpart centering configuration 174 b is thus once again embodied asa recess. In contrast to the first embodiment, in the secondexemplifying embodiment centering stem 160 a not only projects axiallyinto connecting flange 174 but passes axially completely through it.

The result, as a consequence of the design, is that retaining bolt 178can no longer impinge upon connecting flange 174 directly with axialforce and displace it into the operating position, or retain millingdrum 132 axially in the operating position via connecting flange 174. Inthe second embodiment, an axial force transfer between retaining bolt178 and connecting flange 174 connected rigidly to milling drum 132occurs with interposition of an auxiliary component 186 between bolthead 178 b and connecting flange 174. Auxiliary component 186 isadvantageously part of non-locating bearing 176, and serves in thatcontext as a bracing component for the inner ring of the rolling bearingof non-locating bearing 176. Auxiliary component 186 is braced firstlyagainst bolt head 178 b, and then against connecting flange 174.

What is stated above in conjunction with the sliding of non-locatingbearing 76 or non-locating bearing assembly 85 onto bearing stem 74 aand in conjunction with the pulling of non-locating bearing 76 ornon-locating bearing assembly 85 off bearing stem 74 a, by way of apivoting movement of non-locating bearing 76 or non-locating bearingassembly 85 together with side door 30 a, also applies to such slidingor pulling of non-locating bearing 176, in particular of non-locatingbearing subassembly 185, respectively onto and off centering stem 160 a,which interacts with auxiliary component 186 for rotational mounting ofmilling drum 132 in the same way as bearing stem 74 a of the firstembodiment.

In addition, in the second embodiment a central hydraulic cylinder isnot provided; instead several, for example three, hydraulic cylinders162 are arranged with a (preferably equidistant) distribution arounddrive axis A in a circumferential direction and with a (preferablyidentical) radial spacing from drive axis A. Because each of thehydraulic cylinders 162 now needs to supply only a third of the forceoriginally to be applied by central hydraulic cylinder 162 alone, eachof the hydraulic cylinders 162 can advantageously end up being smallerthan central hydraulic cylinder 162 of the first embodiment. There are,however, more of them.

With hydraulic cylinders 162, milling drum 132 can again be movedaxially in a direction toward the operating position, preferably intothe operating position, with corresponding rear engagement componentsbeing arranged at the free longitudinal end of piston rod 163 (notdepicted). Milling drum 132 can likewise be hydraulically moved axiallyout of the operating position.

FIG. 8 shows, once again with reference to the first exemplifyingembodiment, the advantageous use of a release component 88. With the aidof release component 88, milling drum 32 can be released axially out ofits operating position from the locating bearing-side longitudinal end46 a of drive configuration 46, and pulled off, by way of a singlecentral force engagement. Release component 88 can therefore be used,alternatively to hydraulic cylinder or cylinders 62 and 162, to movemilling drum 32 out of the operating position.

In FIG. 8, milling drum tube 42 and thus milling drum 32 have alreadybeen moved axially out of the operating position by the use of releasecomponent 88 so that centering stem 60 a, constituting a centeringconfiguration, no longer centers counterpart centering configuration 74b on connecting flange 74. Milling drum tube 42 is therefore no longercoaxial with drive axis A of drive configuration 46.

The use of release component 88 on the drive assembly or millingassembly of FIG. 8 will be described not only with reference to FIG. 8but also with reference to release component 88 shown in isolation inFIG. 9.

As is evident from FIG. 9, release component 88 extends along a releasecomponent axis LA that, when utilization of release component 88 begins,is preferably coaxial with drive axis A of drive configuration 46 andwith rotation axis R of milling drum 32.

Release component 88 comprises a cooperating configuration 88 a, forexample in the form of an external thread, that can be bolted intobearing stem 74 a of connecting flange 74. Bearing stem 74 a has forthat purpose a passthrough opening 74 d, passing axially through it,through which counterpart centering configuration 74 b in the form of acentering recess is reachable. At the longitudinal end region locatedremotely from centering recess 74 b, bearing stem 74 a has, inpassthrough opening 74 d, internal thread 74 e that can be brought intobolting engagement with external thread 88 a (cooperating configuration)of release component 88 so that release component 88 on the one hand canbe secured on a component connected rigidly to milling drum 32, and onthe other hand can be advanced axially relative thereto in definedfashion.

At its longitudinal end that is located remotely from driveconfiguration 46 in the utilization state, i.e. when cooperatingconfiguration 88 a is bolted into internal thread 74 e, releasecomponent 88 comprises a torque-transferring configuration 88 b, forexample in the form of a hex head tool engagement configuration and/or ahex socket tool engagement configuration. Preferably both toolengagement configurations are implemented on torque-transferringconfiguration 88 b. Torque can be introduced into release component 88at this torque-transferring configuration 88 b while release component88 is in use on earth working machine 10, in order to move saidcomponent axially relative to milling drum 32 with the aid ofcooperating configuration 88 a. A torque wrench or a mechanized torquewrench can engage onto torque-transferring configuration 88 b.

With a correspondingly axially protruding conformation of thecounterpart bracing component or at least of a counterpart bracingregion interacting with a bracing region of the bolting moment bracingarrangement, the bolting moment bracing arrangement can also be employedfor torque bracing of the release component. The working apparatus canthen be pushed off the drive configuration without tools, except for arelease component and bolting moment bracing arrangement. At the least,the torque required for pushing it off does not necessarily have to beapplied manually by an operator. Advantageously, the release componenttherefore comprises a tool engagement configuration (here:torque-transferring configuration 88 b) identical to the bolt componentof the bolt arrangement (here: retaining bolt 78), so that theengagement region of the bolting moment bracing arrangement also fitsonto the tool engagement configuration of the release component.

A shank portion 88 c is adjacent to cooperating configuration 88 a atthe latter's longitudinal end located oppositely fromtorque-transferring configuration 88 b. To reduce the weight of releasecomponent 88, shank portion 88 c is preferably embodied in tubularfashion, i.e. is radially internally hollow. At that longitudinal end ofshank portion 88 c which is located oppositely from cooperatingconfiguration 88 a, release component 88 comprises an abutment portion88 d that can be embodied, for example, as a disk, in particular anannular disk, projecting radially beyond shank portion 88 c. Byadvancing, release component 88 can be brought into abutting engagementat abutment portion 88 d with drive configuration 46, here in particularinto abutting engagement with a longitudinal end region of centeringstem 60 a of cover 60. Internal thread 74 e is thus a fastening and/oradvancing configuration within the meaning of the introductory part ofthe description.

Once abutting engagement has been established between abutment portion88 d and drive configuration 46, connecting flange 74 that comprisesfastening and/or advancing configuration 74 e, and is fixedly connectedto milling drum 32 or to milling drum tube 42, can be caused to moveaxially relative to drive configuration 46 by further introduction oftorque into torque-transferring configuration 88 b.

Depending on the transfer of movement and force between cooperatingconfiguration 88 a and fastening and/or advancing configuration 74 e,for example as a function of the pitch of the thread that is used, alarge axial force, with which even a dirt-caked milling drum 32 can beaxially released from drive configuration 46, can be generated at thesite of the abutting engagement of abutment portion 88 d against driveconfiguration 46.

Once such a dirt jam has been released, i.e. once milling drum 32 hasbeen made axially movable relative to drive configuration 46, theapplied force necessary for axial removal of milling drum 32 from driveconfiguration 46 can be reduced to the usual level known for moving themassive components, and can be managed with usual methods known per se.

As is evident from FIG. 8, release component 88 can also be embodied tobe continuously hollow, i.e. as a tubular release component, so thatdrive configuration 46, or at least components thereof, can beaccessible, even during utilization of release component 88, through anopening that passes through release component 88 along its releasecomponent axis LA. Like bolting moment bracing arrangement 82, releasecomponent 88 is preferably embodied in one piece.

Lastly, FIG. 10 depicts a third embodiment that is intended simply toshow that central retaining bolt 278 can also be bolted to piston rod263 of hydraulic cylinder 262 for axial positional retention of millingdrum 32 on drive configuration 46.

Components and component portions identical and functionally identicalto those of the first embodiment are labeled in the third embodimentwith the same reference characters but incremented by 200. The thirdembodiment of FIG. 10 will be explained here only insofar as it differsfrom the first embodiment to an extent essential in terms of theinvention.

The third embodiment depicted in FIG. 10, having retaining bolt 278threaded into piston rod 263, is of course also applicable to the designof the second embodiment in which centering stem 60 a and bearing stem74 a are implemented in a single component. All that is then necessaryis for bolt head 278 b to brace against an auxiliary component thattransfers force from bolt head 278 b onto a component rigidly connectedto milling drum 232, as is the case in FIG. 7 with auxiliary component186. A component that is present in any case, for example a portion ofnon-locating bearing 276, is once again preferably used as an auxiliarycomponent.

The approach in accordance with the third embodiment as shown in FIG. 10has the advantage that milling drum 232 can be pulled axially onto thedrive configuration and conveyed into the operating position, and alsopushed axially off drive configuration 246 and removed from theoperating position, using hydraulic cylinder 262. For both installationand deinstallation of milling drum 232, the axial forces required forthe axial movement of milling drum 232 are furnished by hydrauliccylinder 262. Axial positional retention with the aforementioned veryhigh torque is once again accomplished, as described in conjunction withFIGS. 4 to 7, thanks to bolting moment bracing arrangement 82, 182 thatinteracts with counterpart bracing component 84, and with anintroduction of torque on the locating bearing side of driveconfiguration 246 either by internal combustion engine 39 or by aseparate rotational drive (including a manual one, if desired) that, ashas already been described above, can be temporarily couplable to acoupling configuration 57 (see FIG. 2) of the drive torque-transferringarrangement for torque transfer.

A preferred embodiment of a bearing component 90 which makes it easierto slide a non-locating bearing 76, 176, 276, in particular anon-locating bearing assembly 85, 185, 285, onto a bearing stem 74 a,160 a, 274 a and to pull it off therefrom, by a pivoting movementtogether with a side door 30 a, 130 a, 230 a, will be described below inconjunction with FIGS. 11A to 14.

A bearing component 90 having a bearing stem 74 a is shown by way ofexample. The statements made below for bearing stem 74 a also apply tothe conformation, interacting with bearing assembly 185, of centeringstem 160 a.

FIG. 11A depicts a separately handleable bearing component 90 and showsin isolation, in a side view, connecting flange 74 already depicted inFIG. 6 having bearing stem 74 a protruding therefrom. FIG. 11B shows thesame bearing component 90 in a longitudinal section view that containscentral bearing stem axis Z of bearing stem 74 a. With milling drum 32in the operational position, bearing stem axis Z ideally coincidescollinearly with rotation axis R and with drive axis A.

Bearing component 90, preferably embodied in one piece, radiallyexternally comprises a plurality of passthrough openings 74 f into whichthe aforementioned threaded studs 72 can be threaded in order to connectconnecting flange 74, and thus bearing component 90, nonrotatably toconnecting ring 70 and thus to milling drum tube 42. Passthroughopenings 74, which alternatively but not preferably can also be blindopenings, are preferably all located at the same radial distance frombearing stem axis Z, and are preferably at the same angular distancefrom one another (see FIG. 12).

Three recesses 74 c, for positively engaging torque-transferringreception as described above of pins 80 nonrotatably connected to cover60, are preferably also embodied equidistantly in terms of angle but ata shorter distance from bearing stem axis Z than passthrough openings 74f.

Bearing component 90 comprises, on its side having stem 74 a, acircumferential projection 74 i that is interrupted only by recesses 74c. As is evident from FIG. 6, this projection 74 i serves to centerbearing component 90 with reference to connecting ring 70. Acomparatively small projection distance for projection 74 i, as comparedwith the protrusion distance of stem 74 a, is therefore sufficient.

Bearing stem 74 a comprises two cylindrical bearing surfaces 74 g and 74h against which hollow-cylindrical counterpart bearing surfaces ofnon-locating bearing assembly 85, more precisely of auxiliary component86, circumferentially abut when milling drum 32 is in the operationalstate. A first cylindrical bearing surface 74 g is farther fromconnecting flange 74, which constitutes an exemplifying protrusionstructure from which bearing stem 74 a protrudes, than secondcylindrical bearing surface 74 h. With these two cylindrical bearingsurfaces, milling drum 32 can be mounted with sufficient accuracy forrotation around rotation axis R. To make it easier to pull non-locatingbearing assembly 85 off bearing stem 74 a, and to slide it thereonto, bymeans of a pivoting movement of non-locating bearing assembly 85together with side door 30 a, first cylindrical bearing surface 74 g hasa smaller diameter than second cylindrical bearing surface 74 h.

As a very general principle, the two cylindrical bearing surfaces canhave different axial lengths, the smaller-diameter cylindrical bearingsurface, in this instance bearing surface 74 g, then preferably beingthe axially longer one.

Also preferably, the axial spacing ab between first cylindrical bearingsurface 74 g and second cylindrical bearing surface 74 h is greater thanthe radial spacing rb between those surfaces.

Bearing stem 74 a preferably tapers toward its free longitudinal end 74k located remotely from protrusion structure 74, as a rule in stepsbecause of cylindrical bearing surfaces 74 g and 74 h, the degree oftaper preferably increasing with increasing distance from protrusionstructure 74. In the preferred embodiment of bearing component 90 or 90′depicted in FIGS. 11 and 13, this becomes evident in the axial portion,relevant for sliding non-locating bearing assembly 85 on together withside door 30 a during a pivoting movement, that extends fromlongitudinal end 74 h 1, located axially closer to protrusion structure74, of second cylindrical bearing surface 74 h to free longitudinal end74 k of bearing stem 74 a. The bearing stem can be embodied in such away that the degree of taper firstly decreases with increasing distancefrom protrusion structure 74 in a region located closer to protrusionstructure 74 than to longitudinal end 74 k, and increases, as the freeaxial longitudinal end 74 k is approached, in a region located closer tolongitudinal end 74 k than to protrusion structure 74.

This axial portion is embodied in such a way that a first notional coneK1, constituting a first osculating circle S1, comprises an outercircumferential line of free longitudinal end 74 k. Cone K1 abutstangentially against this first osculating circle S1, and extends fromthere toward first cylindrical bearing surface 74 g. Cone K1 abutstangentially against a second osculating circle S2 on the outer surfaceof bearing stem 74 a. Osculating circle S2 is located axially betweenfirst osculating circle S1 and axial end 74 g 2, located closer to freelongitudinal end 74 k, of first cylindrical bearing surface 74 g. Firstnotional cone K1 has an opening angle α.

A second notional cone K2 proceeds from axial end 74 g 2, located closerto free longitudinal end 74 k, of first cylindrical bearing surface 74g, constituting its first osculating circle or starting circle S3, andextends to a second osculating circle S4 on the outer surface of bearingstem 74 a, against which cone K2 abuts tangentially. This osculatingcircle S4 is located axially between axial end 74 g 2 and axial end 74 h2, located closer to free longitudinal end 74 k, of second cylindricalbearing surface 74 h. Second notional cone K2 abuts tangentially againstosculating circle S4 but not against osculating circle or startingcircle S3, and has an opening angle β.

Bearing stem 74 a is embodied in such a way that the opening angle α offirst notional cone K1 is larger than the opening angle β of secondnotional cone K2.

First cylindrical bearing surface 74 g extends axially from axial end 74g 1 located closer to the protrusion structure, to axial end 74 g 2located closer to free longitudinal end 74 k. The distance between axialend 74 g 2, located closer to free longitudinal end 74 k, of firstcylindrical bearing surface 74 g and free longitudinal end 74 k canitself be shorter than the distance between the two axial ends 74 h 2and 74 g 2 located closer to free longitudinal end 74 k.

A similar design is selected for the conformation of the counterpartcentering configuration in the form of counterpart centering recess 74b. Counterpart centering recess 74 b preferably has two recess portions74 b 1 and 74 b 2 located axially one behind another in a protrusiondirection of bearing stem 74 a, i.e. the direction in which centeringstem 60 a penetrates into counterpart centering recess 74 b.

With milling drum 32 in the operational state, the larger-diameter maincentering recess portion 74 b 1, which is located closer to drive axialend 32 a of milling drum 32, provides the main centering, relative todrive configuration 46, of bearing configuration 90 and thus of thataxial portion of milling drum 32 which is located closer to retentionaxial end 32 b. The smaller-diameter pre-centering recess portion 74 b2, located farther from drive axial end 32 a, likewise providespre-centering of milling drum 32 relative to drive configuration 46before milling drum 32 reaches its operating position, for example inthe preparation position located axially remotely from the operatingposition.

Centering stem 60 a preferably also comprises two axial portions havingdiameters of different sizes, the larger-diameter one of which,constituting main centering stem portion, is in abutment against thecircumferential wall of main centering recess portion 74 b 1 whenmilling drum 32 is in the operating position. The smaller-diameter axialportion of centering stem 60 a, constituting a pre-centering stemportion, has already begun to enter pre-centering recess portion 74 b 2before the main centering stem portion is introduced into main centeringrecess portion 74 b 1. A larger radial clearance exists between thesmaller-diameter pre-centering stem portion of centering stem 60 a andthe circumferential wall of pre-centering recess portion 74 b 2 thanbetween the larger-diameter main centering stem portion of centeringstem 60 a and the circumferential wall of main centering recess portion74 b 1. Centering recess 74 b can thus be securely and reliably centeredon centering stem 60 a even if, at the beginning of a sliding-onmovement of milling drum 32 onto drive configuration 46, a largepositional discrepancy exists between bearing stem axis Z and a centrallongitudinal axis of centering stem 60 a.

To allow even a large positional discrepancy of this kind to be managedat the beginning of the sliding-on movement, pre-centering recessportion 74 b 2 is preferably embodied to be axially longer than maincentering recess portion 74 b 1. Pre-centering recess portion 74 b 2 ispreferably axially longer than main centering recess portion 74 b 1 byan amount that is greater than the difference value of the radialspacing sb between the two circumferential walls of centering recessportions 74 b 1 and 74 b 2. The axial spacing ib of the two centeringrecess portions 74 b 1 and 74 b 2 from one another is also preferablysmaller than the radial spacing sb between their circumferential walls.

Centering recess 74 b therefore also tapers from its longitudinal end,located closer to drive axial end 32 a, toward internal thread 74 e. Thedegree of taper of centering recess 74 b decreases with increasing axialdistance from its opening located closer to drive axial end 32 a.

In accordance with a preferred embodiment depicted in FIGS. 11A and 11B,the taper of centering recess 74 b is preferably such that a firstvirtual cone K3, which abuts respectively against the edges, locatedaxially closest to drive axial end 32 a, R1 of main centering recessportion 74 b 1 and R2 of pre-centering recess portion 74 b 2, has alarger opening angle γ than a second virtual cone K4 that abuts on theone hand against edge R2, located axially closest to drive axial end 32a, of pre-centering recess portion 74 b 2, and on the other hand againstan edge R3, located closest to drive axial end 32 a, of a radialshoulder 74 d 1, following pre-centering recess portion 74 b 2 axiallyin a penetration direction of centering stem 60 a, of centering recess74 b or of passthrough opening 74 d of which centering recess 74 b is apart. The opening angle of second virtual cone K4 is labeled δ in FIG.11 b.

In the exemplifying embodiment depicted, the opening angle γ of firstvirtual cone K3 is slightly (between approximately 2° and 7°) largerthan the opening angle α of first notional cone K1 described above. Theopening angle δ of second virtual cone K4 is furthermore slightly(approximately 2° to 4°) smaller than the opening angle β of secondnotional cone K2 described above.

FIGS. 13 and 14 depict a modified embodiment of bearing component 90.

Components and component portions identical and functionally identicalto those in FIGS. 11 and 12 have the same reference characters in FIGS.13 and 14 but with an apostrophe added. The modified embodiment of FIGS.13 and 14 will be explained below only insofar as it differs from theembodiment of FIGS. 11 and 12, to the description of which reference isotherwise additionally made for an explanation of the embodiment ofFIGS. 13 and 14.

In the axial portion that extends from longitudinal end 74 h 1′, locatedcloser to the drive axial end, of second cylindrical bearing surface 74h′ to free axial longitudinal end 74 k′, bearing stem 74 a′ of bearingcomponent 90′ has qualitatively the same external conformation asbearing stem 74 a of bearing component 90. The statements made withregard to bearing stem 74 a of bearing component 90 of FIGS. 11 and 12therefore also apply to bearing stem 74 a′ of bearing component 90′ ofFIGS. 13 and 14.

Centering recess 74 b′ also has qualitatively the same conformation ascentering recess 74 b of bearing component 90 of FIGS. 11 and 12. Hereas well, the statements made with regard to bearing component 90 applywithout modification to bearing component 90′.

An essential difference between bearing components 90 and 90′ is thatconnecting flange 74′ of bearing component 90′ has a smaller diameterand a radial step 74 m′.

Radial step 74 m′ is functionally similar to protrusion 74 i of bearingcomponent 90, but differs appreciably in terms of where it is arranged.A protrusion 74 i is therefore not embodied on bearing component 90′between connecting flange 74′ and bearing stem 74 a′ that protrudes fromit.

As a result of radial step 74 m′ embodied on that side of connectingflange 74′ which is located closer to drive axial end 32 a, bearingcomponent 90′ can be inserted, as depicted in FIG. 13A, into acomplementarily stepped recess of connecting ring 70′ in such a way thatthe end face, located closer to retention axial end 32 b, of connectingflange 74′, from which bearing stem 74 a′ axially protrudes, can bearranged flush with an end face, facing in the same direction, ofconnecting ring 70′. Radial step 74 m′ can furthermore be axiallydimensioned in such a way that that longitudinal end of bearingcomponent 90′ which is located closer to drive axial end 32 a is alsoarranged flush with that end face of connecting ring 70 which faces inthe same direction.

Because of the smaller radial extent of connecting flange 74′, recesses74 c′ are not embodied entirely in bearing component 90′ but instead areapparent there only as arc-shaped sub-recesses that form a completerecess 74 c, into which a pin 80 of drive configuration 46 can penetratein torque-transferring fashion, only when supplemented withcorresponding complementary sub-recesses in connecting ring 70′.

Again because of the smaller radial extent of connecting flange 74′,passthrough openings 74 f for fastening bearing component 90′ onconnecting ring 70′ are located radially farther inward, so that theyare only in portions arranged equidistantly from one another in acircumferential direction. No passthrough openings 74 f′ are providedwhere sub-recesses 74 c′ are embodied.

Leaving aside the earth working machine claimed later on, the subjectmatters disclosed below, relating to a replaceable milling drum for anearth working machine, are also of interest to the Applicant as beingworthy of protection. The Applicant reserves the right to claim one orseveral of the subject matters defined below at a later point in time:

1. A replaceable milling drum (32; 232) for an earth working machine(10) such as a road milling machine, recycler, stabilizer, or surfaceminer, which extends between a drive axial end (32 a) and a retentionaxial end (32 b; 232 b) located oppositely from the drive axial end (32a) and is embodied to radially externally surround a drive configuration(46; 246) of the earth working machine (10) in the operationally mountedstate, the milling drum (32; 132; 232) being retainable in itsoperational position, against axial displacement, by a central boltarrangement (78; 278), accessible in the region of its retention axialend (32 b; 232 b), having a bolt axis collinear with the centralapparatus axis (R) of the milling drum (32; 232),

a bearing stem (74 a; 74 a′; 274 a) located in a region closer to theretention axial end (32 b; 232 b) than to the drive axial end (32 a)being provided, which stem protrudes from a protrusion structure (74;74′; 274) carrying it and extends in an axial direction taperingly in adirection away from the drive axial end (32 a), the bearing stem (74 a;74 a′; 274 a) comprising at least two cylindrical bearing surfaces (74g, 74 h; 74 g′, 74 h′) at an axial distance from one another withrespect to the central apparatus axis (R), which, with the milling drum(32; 232) in the operational state, are surrounded with zero clearanceby hollow-cylindrical counterpart bearing surfaces of an earth workingmachine-side non-locating bearing (76; 276), the cylindrical bearingsurface (74 g; 74 g′) located axially farther from the protrusionstructure (74; 74′; 274) having a smaller diameter than the cylindricalbearing surface (74 h; 74 h′) located axially closer to the protrusionstructure (74; 74′; 274), and/or

the milling drum (32; 232) comprising, at a region located closer to theretention axial end (32 b; 132 b; 232 b) than to the drive axial end (32a), a centering recess (74 b; 74 b′; 274), embodied for positivecentering engagement and connected rigidly to the milling drum (32; 132;232), which tapers in a direction away from the drive axial end (32 a),the centering recess (74 b; 74 b′; 274) being embodied with an openingangle (γ, δ) that decreases in steps along its taper.

2. The replaceable milling drum (32; 232) according to subject matter 1,refined in that the centering recess (74 b; 74 b′; 274) is embodied onthe bearing stem (74 a; 74 a′; 274 a).

3. The replaceable milling drum (32; 232) according to subject matter 1or 2, refined in that the axially tapering conformation of the bearingstem (74 a; 74 a′) is such that the opening angle (α, β) of two notionalenveloping cones (K1, K2), which respectively abut tangentially againsttwo osculating circles (S1, S2, S3, S4) located with an axial spacingfrom one another on the surface of bearing stem (74 a; 74 a′) andsurround an axial portion, located between the osculating circles (51,S2, S3, S4), of the bearing stem (74 a′ 74 a′), is smaller for cones(K2) of osculating circle pairs (S3, S4) located closer to theprotrusion structure (74, 74′).

4. The replaceable milling drum (32; 232) according to subject matter 3,refined in that the opening angle (α) of a first notional cone (K1),whose first osculating circle (S1), located farther from the protrusionstructure (74; 74′), is located at the axial longitudinal end (74 k; 74k′) located remotely from the protrusion structure (74; 74′), and whosesecond osculating circle (S2), located closer to the protrusionstructure (74; 74′), is located axially between the first osculatingcircle (S1) and that axial longitudinal end (74 g 2; 74 g 2′) of thefirst cylindrical surface (74 g; 74 g′) which is located closer to thefree bearing stem longitudinal end (74 k; 74 k′), is at least 1.5 times,preferably at least 2.5 times as large as the opening angle (β) of asecond notional cone (K2) whose first osculating circle (S3), locatedfarther from the protrusion structure (74; 74′), is located at thataxial longitudinal end (74 g 2; 74 g 2′) of the first cylindricalbearing surface (74 g; 74 g′) which is located closer to the freebearing stem longitudinal end (74 k; 74 k′).

5. The replaceable milling drum (32; 232) according to subject matter 4,refined in that the opening angle of the second notional cone is equalto 5° to 15°, particularly preferably 8° to 13°.

6. The replaceable milling drum (32; 232) according to one of thepreceding subject matters, refined in that the centering recess (74 b;74 b′; 274) comprises a main centering recess portion (74 b 1; 74 b 1′)located closer to the drive axial end (32 a) and a pre-centering recessportion (74 b 2; 74 b 2′) located farther from the drive axial end (32a), such that a first virtual cone (K3) that abuts respectively againstthe edges (R1, R2), located axially closest to the drive axial end (32a), of the main centering recess portion (74 b 1; 74 b 1′) and of thepre-centering recess portion (74 b 2; 74 b 2′) has a larger openingangle (γ) than a second virtual cone (K4) that abuts on the one handagainst the edge (R2), located axially closest to the drive axial end(32 a), of the pre-centering recess portion (74 b 2; 74 b 2′) and on theother hand against an edge (R3), located closest to the drive axial end,of a recess (74 d; 74 d′) that axially follows the pre-centering recessportion (74 b 2; 74 b 2′) in a direction away from the drive axial end(32 a) and of which the centering recess (74 b; 74 b′) is a part.

7. The replaceable milling drum (32; 232) according to subject matter 6,refined in that the opening angle (γ) of the first virtual cone (K3) isapproximately 3 to 6 times, particularly preferably 4 to 5 times, largerthan the opening angle (δ) of the second virtual cone (K4).

8. The replaceable milling drum (32; 232) according to subject matter 6or 7, refined in that the opening angle (γ) of the first virtual cone(K3) is equal to between 20° and 40°, particularly preferably between25° and 35°.

9. The replaceable milling drum (32; 232) according to one of subjectmatters 6 to 8, including subject matter 4, refined in that the openingangle (γ) of the first virtual cone (K3) is larger than the openingangle (α) of the first notional cone (K1) described above.

10. The replaceable milling drum (32; 232) according to one of subjectmatters 6 to 9, including subject matter 4, wherein the opening angle(δ) of the second virtual cone (K4) is smaller than the opening angle(β) of the second notional cone (K2) described above.

1-15. (canceled) 16: A replaceable milling drum for an earth workingmachine, comprising: a milling drum tube including a drive axial end anda retention axial end located oppositely from the drive axial end, themilling drum tube having a drive axis about which the milling drum tubeis rotatable; a protrusion structure fixed to the milling drum tube andlocated closer to the retention axial end than to the drive axial end;and a bearing stem protruding from the protrusion structure axially awayfrom the drive axial end, the bearing stem having an outer surfaceincluding at least first and second cylindrical bearing surfaces axiallyspaced from each other, a furthest one of the cylindrical bearingsurfaces from the drive axial end having a smaller diameter than a nextfurthest one of the cylindrical bearing surfaces from the drive axialend, the bearing stem having a central opening therethrough co-axialwith the drive axis. 17: The replaceable milling drum of claim 16,wherein: an axially tapering conformation of the outer surface of thebearing stem is such that an opening angle (α, β) of first and secondnotional enveloping cones (K1, K2), which respectively abut tangentiallyagainst two osculating circles (S1, S2, S3, S4) located with an axialspacing from one another on the outer surface of the bearing stem andsurround an axial portion, located between the osculating circles (S1,S2, S3, S4), of the bearing stem, is smaller for the second notionalenveloping cone (K2) of osculating circle pair (S3, S4) located closerto the protrusion structure. 18: The replaceable milling drum of claim17, wherein: the opening angle (α) of the first notional enveloping cone(K1), whose first osculating circle (S1), located farther from theprotrusion structure, is located at an axial longitudinal free end ofthe bearing stem located remotely from the protrusion structure, andwhose second osculating circle (S2), located closer to the protrusionstructure is located axially between the first osculating circle (S1)and an axial longitudinal end of the first cylindrical bearing surfacewhich is located closer to the axial longitudinal free end of thebearing stem, is at least 1.5 times as large as the opening angle (β) ofthe second notional enveloping cone (K2) whose first osculating circle(S3), located farther from the protrusion structure is located at theaxial longitudinal end of the first cylindrical bearing surface which islocated closer to the axial longitudinal free end of the bearing stem.19: The replaceable milling drum of claim 18, wherein: the opening angle(α) of the first notional enveloping cone (K1) is at least 2.5 times aslarge as the opening angle (β) of the second notional enveloping cone(K2). 20: The replaceable milling drum of claim 18, wherein: the openingangle (β) of the second notional enveloping cone (K2) is in a range offrom about 5° to about 15°. 21: The replaceable milling drum of claim18, wherein: the opening angle (β) of the second notional envelopingcone (K2) is in a range of from about 8° to about 13°. 22: Thereplaceable milling drum of claim 16, wherein: the bearing stem furtherincludes a centering recess open toward the drive axial end andincluding an opening angle decreasing in steps so that the centeringrecess tapers in a direction away from the drive axial end, thecentering recess forming a portion of the central opening. 23: Thereplaceable milling drum of claim 22, wherein: the centering recesscomprises a main centering recess portion located closer to the driveaxial end and a pre-centering recess portion located farther from thedrive axial end, such that a first virtual cone (K3) that abutsrespectively against the edges (R1, R2), located axially closest to thedrive axial end, of the main centering recess portion and of thepre-centering recess portion has a larger opening angle (γ) than asecond virtual cone (K4) that abuts on the one hand against the edge(R2), located axially closest to the drive axial end of thepre-centering recess portion and on the other hand against an edge (R3),located closest to the drive axial end, of a recess that axially followsthe pre-centering recess portion in a direction away from the driveaxial end and of which the centering recess is a part. 24: Thereplaceable milling drum of claim 23, wherein: the opening angle (γ) ofthe first virtual cone (K3) is in a range of from about 3 to about 6times larger than the opening angle (δ) of the second virtual cone (K4).25: The replaceable milling drum of claim 24, wherein: the opening angle(γ) of the first virtual cone (K3) is in a range of from about 20° toabout 40°. 26: The replaceable milling drum of claim 24, wherein: theopening angle (γ) of the first virtual cone (K3) is in a range of fromabout 25° to about 35°. 27: The replaceable milling drum of claim 23,wherein: the opening angle (γ) of the first virtual cone (K3) is in arange of from about 4 to about 5 times larger than the opening angle (δ)of the second virtual cone (K4). 28: The replaceable milling drum ofclaim 22, wherein: an axially tapering conformation of the outer surfaceof the bearing stem is such that an opening angle (α, β) of first andsecond notional enveloping cones (K1, K2), which respectively abuttangentially against two osculating circles (S1, S2, S3, S4) locatedwith an axial spacing from one another on the outer surface of bearingstem and surround an axial portion, located between the osculatingcircles (S1, S2, S3, S4), of the bearing stem, is smaller for the secondnotional enveloping cone (K2) of the osculating circle pair (S3, S4)located closer to the protrusion structure; and the opening angle (γ) ofthe first virtual cone (K3) is larger than the opening angle (α) of thefirst notional enveloping cone (K1). 29: The replaceable milling drum ofclaim 28, wherein: the opening angle (δ) of the second virtual cone (K4)is smaller than the opening angle (β) of the second notional envelopingcone (K2). 30: A replaceable milling drum for an earth working machine,comprising: a milling drum tube including a drive axial end and aretention axial end located oppositely from the drive axial end, themilling drum tube having a drive axis about which the milling drum tubeis rotatable; a protrusion structure fixed to the milling drum tube andlocated closer to the retention axial end than to the drive axial end;and a bearing stem protruding from the protrusion structure axially awayfrom the drive axial end, the bearing stem including a central openingtherethrough co-axial with the drive axis, the bearing stem furtherincluding a centering recess open toward the drive axial end andincluding an opening angle decreasing in steps so that the centeringrecess tapers in a direction away from the drive axial end, thecentering recess forming a portion of the central opening. 31: Thereplaceable milling drum of claim 30, wherein: the centering recesscomprises a main centering recess portion located closer to the driveaxial end and a pre-centering recess portion located farther from thedrive axial end, such that a first virtual cone (K3) that abutsrespectively against the edges (R1, R2), located axially closest to thedrive axial end, of the main centering recess portion and of thepre-centering recess portion has a larger opening angle (γ) than asecond virtual cone (K4) that abuts on the one hand against the edge(R2), located axially closest to the drive axial end of thepre-centering recess portion and on the other hand against an edge (R3),located closest to the drive axial end, of a recess that axially followsthe pre-centering recess portion in a direction away from the driveaxial end and of which the centering recess is a part. 32: Thereplaceable milling drum of claim 31, wherein: the opening angle (γ) ofthe first virtual cone (K3) is in a range of from about 3 to about 6times larger than the opening angle (δ) of the second virtual cone (K4).33: The replaceable milling drum of claim 32, wherein: the opening angle(γ) of the first virtual cone (K3) is in a range of from about 20° toabout 40°. 34: The replaceable milling drum of claim 32, wherein: theopening angle (γ) of the first virtual cone (K3) is in a range of fromabout 25° to about 35°. 35: The replaceable milling drum of claim 31,wherein: the opening angle (γ) of the first virtual cone (K3) is in arange of from about 4 to about 5 times larger than the opening angle (δ)of the second virtual cone (K4).